By Arthur J. Whiteman
By Walter Schumann
By Ronald Bonewitz
By Andrew Ross
By Natural History Museum
By Ian Mercer, G. Cressey (Researcher in Mineral Sciences, The Natural History Museum, London)
By Paul Steinhardt
By Schluter, Thomas, Trauth, Martin H.
By Best, Myron G.
By Adams, A.E., Mackenzie, W.S., Guilford, C.
By Smith, Herbert Gladstone, Wells, Maurice Kingsley
By Atwood, Fred
By Dr J. Kourimsky
By Nriagu, Jerome O., Nieboer, Evert
By Maurice E. Tucker
By Brindley, G. W., Brown, G. C.
By Vernon, Ron H.
By Brian Simpson
By Winter, John D.
By Bennett, Richard, Hulbert, Matthew
By Bartholomew, Mervin J., Hyndman, Donald W., Mogk, David W., Mason, Robert
By Lima-de-Faria, J.
By Brady, Barry H.G., Brown, E. T.
By Manning, D.A.C., Hall, P.L., Hughes, C.R.
By Pitcher, W.S.
By Pulinets, Sergey, Boyarchuk, Kyrill
By Varentsov, I.M.
By Shelley, D.
By Sunagawa, Ichiro