1. Abelson, P. H., and Hare, P. E.: 1969, Recent Amino Acids in the Gunflint Chert,Carnegie Inst. Wash. Year Book 67, 208?210.
2. Akiyama, M.: 1978, Epimerization of L-isleucine on Na-montmorillonite and its Implication to Precambrian Chemical Fossils, in H. Noda (ed.),Origin of Life, Center for Acad. Pub., Tokyo, pp. 541?545.
3. Bada, J. L. and Schroeder, R. A.: 1975, Amino Acid Racemization and Their Geochemical Implication,Naturwissenschaften 62, 71?79.
4. Calvin, M.: 1969,Chemical Evolution, Oxford Univ. Press, London, 278 pp.
5. Meddelelser om Gronland;W. S. Davies,1963