APA-čujuhus (7. p.)
(1991). Science year 1991: A review of science and technology during the 1990 school year. World Book, Inc.
Chicago-čujuhus (17. p.)
Science Year 1991: A Review of Science and Technology During the 1990 School Year. Chicago: World Book, Inc, 1991.
MLA-čujuhus (9. p.)
Science Year 1991: A Review of Science and Technology During the 1990 School Year. World Book, Inc, 1991.
Muitte dárkkistit čujuhemiid riektatvuođa, ovdal go geavahat daid iežat deavsttas.