M.-P. Véron-Cetty
and P. Véron
May 2001
Observatoire de Haute Provence, CNRS
F-04870 Saint-Michel l'Observatoire
The recent publication of the first release of the 2dF quasar catalogue
(Croom et al. 2001) containing nearly 10 000 new QSOs, almost doubling the
number of such objects known, led us to prepare an updated version of our
catalogue of quasars and active nuclei which now contains 23 760
quasars, 608 BL Lac objects and 5 751 active galaxies (of which 2 765 are
Seyfert 1).
Like the ninth edition, it includes
position and redshift as well as photometry (U, B, V) and 6 and 11 cm flux
densities when available.
1 Summary
We also give a list of all known lensed and double quasars.
2 Introduction
The first catalogue of quasars was published in 1971 by De Veny et al.
It contained 202 objects for which redshifts were published prior to june 1971.
The number of known quasars has since steadily increased, but the
recent release of the ``2dF QSO redshift survey" (Croom et al. 2001) has almost
doubled this number which is expected to increase again dramatically when the final
2dF catalogue will be published at the end of 2002 containing ~ 15 000
new QSOs and when the
``Sloan Digital Sky Survey" which should discover
~ 100 000 QSOs will be completed in about 2004 (Fan et al. 1999)
QSO | BL Lac | Seyfert 1 | reference |
2 251 | 190 | Véron-Cetty & Véron 1984 | |
2 835 | 73 | 236 | Véron-Cetty & Véron 1985 |
3 473 | 84 | 258 | Véron-Cetty & Véron 1987 |
4 169 | 117 | 358 | Véron-Cetty & Véron 1989 |
6 225 | 162 | 575 | Véron-Cetty & Véron 1991 |
7 383 | 171 | 695 | Véron-Cetty & Véron 1993 |
8 609 | 220 | 888 | Véron-Cetty & Véron 1996 |
11 358 | 357 | 1 111 | Véron-Cetty & Véron 1998 |
13 214 | 462 | 1 711 | Véron-Cetty & Véron 2000 |
23 760 | 608 | 2 765 | present edition |
In the present edition of this catalogue containing quasars with
measured redshift known to us prior to May 1st, 2001, as in the preceding
editions, we do not give any information about absorption lines or X-ray
properties. But we give the absolute magnitude for each object and, when
available, the 11 and 6 cm flux densities.
This catalogue should not be used for any statistical analysis as it is not complete in any sense, except that it is, hopefully, a complete survey of the literature.
In table 2, we list all confirmed, probable or possible BL Lac objects with or without a measured redshift, without consideration of their absolute magnitude. As better spectra are becoming available, broad emission lines have been detected in a number of objects formerly classified as BL Lac; they have usually been moved to table 1 (Véron-Cetty & Véron, 2000).
The Seyfert 1 galaxies have broad Balmer and other permitted lines; the Seyfert 2 galaxies have Balmer and forbidden lines of the same width. Osterbrock (1977; 1981) has divided the Seyfert galaxies showing broad Balmer lines (Seyfert 1) into five subgroups : Seyfert 1.0, 1.2, 1.5, 1.8 and 1.9 on the basis of the appearance of the Balmer lines. Seyfert 1.0s are ``typical" members of the class, as described by Khachikian & Weedman (1971; 1974), while Seyfert 1.5s are objects intermediate between typical Seyfert 1 and Seyfert 2 galaxies, with an easily apparent narrow Hb profile superimposed on broad wings. The classes Seyfert 1.2 or 1.8 are used to describe objects with relatively weaker and stronger narrow Hb components, intermediate between Seyfert 1.0 and 1.5 and Seyfert 1.5 and 2 respectively. In Seyfert 1.9, although the broad Ha emission is clearly evident, broad Hb cannot be detected with certainty by mere visual inspection of the spectra.
We have adopted the more quantitative classification introduced by Winkler (1992) :
S1.0 | 5.0 | < R | S1.2 | 2.0 | < R < | 5.0 | S1.5 | 0.333 | < R < | 2.0 | S1.8 | R < | 0.333 | broad component visible in Ha and Hb | S1.9 | broad component visible in Ha but not in Hb | S2 | no broad component visible |
where R is the ratio of the total Hb to the [OIII]l5007 fluxes.
Several objects have been found to show extreme spectral variability, changing from Seyfert 1.8 or 1.9 to Seyfert 1. In some cases these changes are consistent with changes in the reddening to the BLR while, in others, they are probably due to real changes in ionizing flux (Goodrich, 1989a; 1995; Tran et al. 1992b). In some Seyfert 2 galaxies, a broad Pa b line has been detected, indicating the presence of a highly reddened broad line region (Goodrich et al. 1994); we call these objects S1i. A number of Seyfert 2 galaxies have, in polarized light, the spectra of Seyfert 1s (Antonucci & Miller, 1985; Miller & Goodrich 1990; Tran et al. 1992a); we call them S1h. Typical full widths at half-maximum of the Balmer lines in Seyfert 1 galaxies lie in the range 2000-6000 km s-1. However, there is a group of active galactic nuclei with all the properties of Seyfert 1 galaxies, but with unusually narrow Balmer lines (Osterbrock & Pogge, 1985; Goodrich, 1989b); they are defined as having the broad component of the Balmer lines narrower than 2000 km s-1 FWHM (Osterbrock, 1987); we call them S1n.
Table 3 lists ``active galaxies" : Seyfert 1, 1.5, 1.8, 1.9, 1h, 1i, 1n, 2, and Liners (as defined by Heckman, 1980) fainter than the above quoted absolute magnitude. A number of galaxies with a nuclear HII region denoting a burst of star formation are also included, the reason being that they have been called Seyfert in the past and later reclassified; we consider it useful to keep trace of these reclassifications to avoid further confusion.
Table 4 lists the objects which once have been believed to be quasars or BL lac objects and are now known to be either stars or normal galaxies.
Table 1 contains 23 760 objects, table 2, 608 , table 3, 5 751 and table 4, 71.
The catalogue is believed to be complete for quasars, BL Lac objects and Seyfert 1 galaxies.
Since the discovery in 1979 by Walsh et al. of the first gravitationally lensed quasar, Q 0957+561, a number of such objects (44) and of physical pairs with separation less than 10" (11) have been found. They are listed in table 5. Mortlock et al. (1999) have stressed the difficulty sometimes encountered in distinguishing lensed quasars from physical pairs.
Tables 1, 2 and 3 give :
1) The most common name of the object.
For the meaning and the sources of the designations see Hewitt &
Burbidge (1987), Fernandez et al. (1983) and Kesteven & Bridle (1977). For
the sources discovered by the ROSAT X-ray satellite, we have used the
following acronyms : RXS for the sources appearing in the All-Sky Bright
Source Catalogue (Voges et al. 1999), 1WGA for the sources published in the
WGACAT catalogue (White et al. 1994) and RX for the others.
When the name is preceded by an *, the object has
not been detected as a radio source, either because it has not been observed
or because it is fainter than the sensitivity limit of the radio telescope
used; there is no uniform upper limit to the flux density of the undetected
objects.
2) The best available J2000 optical or radio coordinates; the J2000 positions have been converted from the B1950 positions using the matrix given by Aoki et al. (1983). No references are given for the sources of these positions. An O or an R following the coordinates means that the position given is either an optical or a radio position measured with an accuracy better than one arc sec. An A means that it is only an approximate position which may be wrong by several arc minutes. The availability of the Digitized Sky Survey (DSS) allows quick measurements of the optical position of any object brighter than ª 19.5 mag. It has already been used to measure the position of several hundred QSOs (Schneider et al. 1992; Bowen et al. 1994; Kirhakos et al. 1994; Véron-Cetty & Véron, 1996). Optical positions with an accuracy better than 2" have also been measured for the 19 369 galaxies in the Zwicky catalogue (Falco et al. 1999) and for the 12 921 UGC galaxies (Cotton et al. 1999).
3) The 6 and 11 cm flux densities (in Jy) with references to the literature. When several measurements are available we took arbitrarily one of them. When a reference is given for the 6 cm flux density but the value of the flux density itself is left blank and there is an * in column 1, only an upper limit is available and this upper limit is not much greater than 1 mJy; in case there is no * in column 1, the reference refers to a detection but at a wavelength other than 6 cm.
4) The redshift as published. An * in front of the redshift means that it has been estimated from a low dispersion slitless spectrum and is of lesser accuracy or even plainly wrong as the emission lines may easily be misidentified. We have given only those values which are described as probable in the original sources and not the possible values.
5) In this column an attempt has been made to classify the objects as follows :
S1 | Seyfert 1 spectrum with broad permitted hydrogen emission lines, without sufficent information for a more detail classification | S1.0, | S1.2, S1.5, S1.8, S1.9, S1i, S1h, S1n (see above). | S2 | Seyfert 2 spectrum defined as having a strong [O III]l 5007 line compared with Hb, together with a [NII]l6584 line of strength comparable with that of Ha. | S3 | Seyfert 3 or Liner as defined by Heckman (1980). Broad Balmer lines are observed in some Liners; they are called S3b. If these broad Balmer lines are only seen in polarized light, they are called S3h. | S or S? | These objects are probably or possibly Seyfert galaxies, but available data are insufficient for a more detailed classification. | H2 | Nuclear HII region, i.e. nucleus of a galaxy with an emission line spectrum similar to that of an emission nebula ionized by hot stars. | HP | A high degree of optical polarization ( > 3%) has been measured (see for instance : Impey et al. 1991; Moore & Stockman, 1984). |
Low redshift quasars are classified as S1 when a good spectrum shows that they are similar to Seyfert 1 galaxies.
In table 2, we find in this column :
BL | for a confirmed BL Lac object. | blank | for a probable BL Lac. | ? | for a possible BL Lac. |
6) The V, B-V and U-B photoelectric or photographic magnitude and
colours, when available.
(the survey of the literature for photographic colours may be incomplete) (an
* in front of the magnitude indicates that the colours and the magnitude are
photographic, while an R or an I indicates a red or an infrared magnitude). Maoz et al. (1993)
have measured homogeneous V magnitudes for 354 QSOs with an
accuracy of ±0.1 mag; they have been included. For a
few objects, the O magnitude, measured on the blue Palomar Sky Survey
plates, or the UK Science
Research Council SRC-J Survey plates, believed to be accurate within ±
0.2 mag., has been extracted from the APS database (Pennington et al. 1993).
For a number of objects we give the O magnitude, extracted from the USNO-A2
catalogue (Monet et al. 1996) or the Cambridge Automated Plate Measuring Machine
(APM) catalogue (Irwin et al. 1994), recalibrated by E. Flesch (private communication);
these magnitudes are flagged with an O.
The O and Johnson B magnitudes are related
by B-O = -(0.27±
0.06) (B-V) (Evans, 1989).
In the other cases, the magnitude given is an estimate as
found in the original publications; these magnitudes are generally quite
inaccurate and inhomogeneous;
they are most often mpg or B magnitudes instead of the Johnson V magnitude.
Much care should be taken when using them for any purpose. Anyway, even when
a photoelectric V magnitude is given, it is not very meaningful as most quasars
are variable. On the other hand, the colours of quasars vary little, so the
listed colours should be accurate. Again, it should be noted that
some of the colours listed are photographic and, therefore, less accurate;
moreover, in each catalogue of photoelectric measurements, the faintest objects
measured are affected by relatively large errors; this too should not be
overlooked. For the galaxies, in table 3, we have chosen the magnitudes and
colours measured in the smallest possible diaphragm (preferentially 16 arcsec)
as we are interested in the nucleus rather than in the galaxy itself.
7) The absolute magnitude MB computed by assuming H0=50 km s-1 Mpc-1, q0=0, and an optical spectral index a equal to 0.3 (defined as S µ n-a) (Francis et al. 1991).
The absolute magnitude is computed as follows : M = m + 5 - 5 log D - k + D m(z) where m is the B magnitude, D = c/H0 A, with A the photometric distance (Terrell, 1977) :
|
z is the redshift taken from column 5; k=-2.5 log(1+z)1-a is the k correction, Dm (z) is a correction to k taking into account the fact that the spectrum of quasars is not strictly a power law of the form S µ n-a, but is affected by emission lines and by the Ly a forest depleting the continuum to the blue of Ly a. Assuming that the spectrum is a power law with a=0.3 may not give the best possible estimate of the k correction (Wisotzki 2000).
The column labelled ``V" gives the V magnitude when B-V is also given in which case we have used B = V+(B-V). When B-V is not given, this column usually gives the B magnitude, unless it is preceded by an R or an I; the R magnitudes have been transformed into the B system by using an average < B-R > =0.57 and the I magnitudes by using < B-I > =1.1 for low z QSOs. When the reference for the magnitude is Maoz et al. (1993), the magnitude is V and we have used < B-V > =0.40.
We list in table 1 those objects which have an absolute magnitude MB brighter than -23; clearly some objects would move from table 1 to table 3 and vice versa if other values for q0 and the spectral index were used or if an accurate B apparent magnitude was available for all objects.The variability may have a similar effect, as well as the size of the diaphragm used for the measurement as the contribution of the underlying galaxy for weak quasars may not be negligible.
8) The next three columns give the reference for the finding chart, the photometry and the redshift respectively. In many cases, the last reference in table 3 is that of the classification of the object (as a Seyfert galaxy or otherwise); in these cases the redshift can usually be found in Palumbo et al. (1983).
9) The B1950 position.
We are grateful to E. Flesch for extracting for us the recalibrated O
magnitudes from the APM and USNO catalogues and to
E. Flesch, F. Ochsenbein and R. Monella for having
brought to our attention a number of errors and omissions in the 8th edition
of this catalogue.
4 Acknowledgements
This research has made use of the APS catalogue of
POSS I database which is supported by the National Science Foundation, the
National Aeronautics and Space Administration, and the University of Minnesota
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Name | Position | zquasar | zlens | sep(") | Ref. |
Lensed QSOs | |||||
UM 673 | 0142-10 | 2.719 | 2.2 | 48 | |
CTQ 414 | 0156-43 | 1.29 | 1.2 | 37 | |
B2 0218+35 | 0218+35 | 0.936 | 0.33 | 11 | |
HE 0230-2130 | 0230-21 | 2.162 | 2.0 | 58 | |
Q J0240-343 | 0238-34 | 1.406 | 6.1 | 50 | |
PKS 0411+05 | 0411+05 | 2.639 | 0.958 | 2.2 | 25,52 |
HE 0512-3329 | 0512-33 | 1.565 | 0.931 | 0.6 | 10 |
B 0712+472 | 0712+47 | 1.339 | 1.27 | 7 | |
MG 0751+2716 | 0748+27 | 3.200 | 0.350 | 52 | |
HS 0818+1227 | 0818+12 | 3.115 | 2.1 | 12 | |
CLASS B0827+525 | 0827+52 | 2.064 | 2.8 | 23 | |
APM 08279+5255 | 0827+52 | 3.87 | 0.4 | 26 | |
RX J0911.4+0551 | 0908+06 | 2.800 | 0.8 | 1 | |
SBS 0909+532 | 0909+53 | 1.377 | 0.830 | 1.11 | 22,30 |
1WGA J09212+4528 | 0917+45 | 1.66 | 0.31 | 6.93 | 41 |
FBQS J0951+2635 | 0948+26 | 1.24 | 1.1 | 45 | |
BRI 0952-01 | 0952-01 | 4.43 | 0.95 | 34 | |
Q 0957+561 | 0957+56 | 1.414 | 0.355 | 6.1 | 9,53 |
Q 1009-0252 | 1009-02 | 2.74 | 1.55 | 16 | |
J 13.03 | 1015-20 | 2.55 | 0.84 | 49 | |
IRAS F10214+4724 | 1021+47 | 2.286 | 46 | ||
B 1030+074 | 1030+07 | 1.535 | 1.56 | 7 | |
HE 1104-1805 | 1104-18 | 2.303 | 0.729 | 3.0 | 28,56 |
PG 1115+080 | 1115+08 | 1.722 | 0.311 | 2.3 | 51,54 |
UM 425 | 1120+01 | 1.465 | 6.5 | 35 | |
TEX 1152+199 | 1152+19 | 1.019 | 0.439 | 1.6 | 42 |
Q 1208+1011 | 1208+10 | 3.803 | 0.45 | 32 | |
87GB 1359+1527 | 1359+15 | 3.235 | 1.7 | 42 | |
H 1413+117 | 1413+11 | 2.546 | 1.4 | 31 | |
HST J14176+5226 | 1415+52 | 3.4 | 3.2 | 4 | |
B 1422+231 | 1422+23 | 3.62 | 0.339 | 1.3 | 43,51 |
Q 1429-008 | 1429-00 | 2.076 | 5.1 | 15 | |
SBS 1520+530 | 1520+53 | 1.855 | 1.6 | 3 | |
Q 1600+434 | 1600+43 | 1.61 | 1.38 | 20 | |
Q 1634.9+26.7 | 1634+26 | 1.961 | 3.8 | 47 | |
FIRST J1633+3134 | 1631+31 | 1.516 | 0.66 | 39 | |
MC 1830-211 | 1830-21 | 2.507 | 0.885 | 0.60 | 27,29 |
TEX 1835-345 | 1835-34 | 2.78 | 1.0 | 55 | |
MG 2019+1127 | 2016+11 | 3.273 | 3.4 | 24 | |
87GB 20451+2632 | 2045+26 | 1.28 | 0.867 | 1.9 | 8 |
Q 2138-431 | 2138-43 | 1.641 | 4.5 | 14 | |
H 2149-2745 | 2149-27 | 2.033 | 1.7 | 57 | |
Q 2237+0305 | 2237+03 | 1.695 | 0.039 | 1.8 | 19 |
Q 2345+007 | 2345+00 | 2.15 | 7.1 | 44 | |
Binary QSOs | |||||
Q 0023+171 | 0023+17 | 0.945 | 4.8 | 18 | |
CT 344 | 0103-27 | 0.848 | 0.3 | 21 | |
PHL 1222 | 0151+04 | 1.91 | 3.3 | 36 | |
CTQ 839 | 0250-33 | 2.24 | 2.1 | 38 | |
Q 1145-071 | 1145-07 | 1.34 | 4.2 | 6 | |
HS 1216+5032 | 1216+50 | 1.450 | 8.9 | 13 | |
RRS IV 26,27 | 1343+26 | 2.030 | 9.5 | 5 | |
RX J16290+3724 | 1627+37 | 0.923 | 4.3 | 33 | |
Q J1643+31 | 1641+32 | 0.586 | 2.3 | 2 | |
Q 2153-2056 | 2153-20 | 1.845 | 7.8 | 17 | |
MGC 2214+3550 | 2212+35 | 0.877 | 3.0 | 40 |
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(7) | Fassnacht & Cohen, 1998 | (36) | Meylan et al. 1990 |
(8) | Fassnacht et al. 1999 | (37) | Morgan et al. 1999 |
(9) | Garrett et al. 1992 | (38) | Morgan et al. 2000 |
(10) | Gregg et al. 2000 | (39) | Morgan et al. 2001 |
(11) | Grundahl & Hjorth, 1995 | (40) | Mu~noz et al. 1998 |
(12) | Hagen & Reimers 2000 | (41) | Mu~noz et al. 2001 |
(13) | Hagen et al. 1996 | (42) | Myers et al. 1999 |
(14) | Hawkins et al. 1997 | (43) | Patnaïk et al. 1992 |
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(16) | Hewett et al. 1994 | (45) | Schechter et al. 1998 |
(17) | Hewett et al. 1998 | (46) | Serjeant et al. 1995 |
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