(1990). Environmental health criteria 97.
Lua i Stíl Chicago (17ú heag.)Environmental Health Criteria 97. 1990.
Lua MLA (9ú heag.)Environmental Health Criteria 97. 1990.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.
Lua APA (7ú heag.)