Leedy, P. Research planning and desing.
Chicago-čujuhus (17. p.)Leedy, Paul. Research Planning and Desing. [Lugar de publicación no identificado].
MLA-čujuhus (9. p.)Leedy, Paul. Research Planning and Desing.
Muitte dárkkistit čujuhemiid riektatvuođa, ovdal go geavahat daid iežat deavsttas.