Wald, G. (1966). Twenty-six afternoons of biology: An introductory laboratory manual (2nd ed.). Addison-Wesley.
Lua i Stíl Chicago (17ú heag.)Wald, George. Twenty-six Afternoons of Biology: An Introductory Laboratory Manual. 2nd ed. Reading, MA: Addison-Wesley, 1966.
Lua MLA (9ú heag.)Wald, George. Twenty-six Afternoons of Biology: An Introductory Laboratory Manual. 2nd ed. Addison-Wesley, 1966.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.