Perl, P. (1978). Cacti and succulents. Time-Life Books.
Lua i Stíl Chicago (17ú heag.)Perl, Philip. Cacti and Succulents. Alexandria, Virginia: Time-Life Books, 1978.
Lua MLA (9ú heag.)Perl, Philip. Cacti and Succulents. Time-Life Books, 1978.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.