1016/S0022-1139(00)81949-1. Baxter, Paul L.; Downs, Anthony J.; Forster, Alan M.; Goode, Michael J.; Rankin, David W. H.; Robertson, Heather E. The molecular
1016/s0022-1139(00)84002-6. Baxter, Paul L.; Downs, Anthony J.; Forster, Alan M.; Goode, Michael J.; Rankin, David W. H.; Robertson, Heather E. The molecular
Nacional/UFRJ, Rio de Janeiro 139. Downs, Alex. 2000. in "Dinosaurs of New Mexico," New Mexico Museum of Natural History Bulletin. Paul GS. (1993) in New Mexico
Chemical Education. 1932, 9 (8): 1386. Bibcode:1932JChEd...9.1386W. doi:10.1021/ed009p1386. Downs, p. 15 Weeks, Mary Elvira. The discovery of the elements.