Willis, G. (2018). Permaculture: Principles and practice (1a. ed.). Larsen and Keller Education.
Chicago-čujuhus (17. p.)Willis, George. Permaculture: Principles and Practice. 1a. ed. Nueva York: Larsen and Keller Education, 2018.
MLA-čujuhus (9. p.)Willis, George. Permaculture: Principles and Practice. 1a. ed. Larsen and Keller Education, 2018.
Muitte dárkkistit čujuhemiid riektatvuođa, ovdal go geavahat daid iežat deavsttas.