ebrary, Inc, & Ludvigsen, R. (1996). Life in stone: A natural history of British Columbia's fossils. UBC Press.
Chicago-čujuhus (17. p.)ebrary, Inc, juo Rolf Ludvigsen. Life in Stone: A Natural History of British Columbia's Fossils. Vancouver, BC: UBC Press, 1996.
MLA-čujuhus (9. p.)ebrary, Inc, juo Rolf Ludvigsen. Life in Stone: A Natural History of British Columbia's Fossils. UBC Press, 1996.
Muitte dárkkistit čujuhemiid riektatvuođa, ovdal go geavahat daid iežat deavsttas.