Cottrell, R. F. (1963). Beyond tomorrow. Southern Publishing Ass.
Chicago-čujuhus (17. p.)Cottrell, Raymond F. Beyond Tomorrow. Southern Publishing Ass, 1963.
MLA-čujuhus (9. p.)Cottrell, Raymond F. Beyond Tomorrow. Southern Publishing Ass, 1963.
Muitte dárkkistit čujuhemiid riektatvuođa, ovdal go geavahat daid iežat deavsttas.