1.
, . Twentieth-century American science fiction writers. Detroit: Gale Research; 1981.
et . Twentieth-century American science fiction writers. Detroit : Gale Research, 21 mai 1981. ISBN 0810309181
Cowart, D., & Wymer Thomas L. (1981). Twentieth-century American science fiction writers: 2 M-Z. Gale Research.
Style de citation MLA (8e éd.)Cowart, David, et Wymer Thomas L. Twentieth-century American Science Fiction Writers: 2 M-Z. Gale Research, 1981.
Attention : ces citations peuvent ne pas être correctes à 100%.