David, D., & Davidescu, V. (1982). Evaluation of fertility by plant and soil analysis. Abacus Press & Tunbridge Wells.
Lua i Stíl Chicago (17ú heag.)David, Davidescu, agus Velicica Davidescu. Evaluation of Fertility by Plant and Soil Analysis. England: Abacus Press & Tunbridge Wells, 1982.
Lua MLA (9ú heag.)David, Davidescu, agus Velicica Davidescu. Evaluation of Fertility by Plant and Soil Analysis. Abacus Press & Tunbridge Wells, 1982.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.