Brown, T. (1997). What is Earth Day? Philippine Star.
Lua i Stíl Chicago (17ú heag.)Brown, Tim. "What Is Earth Day?" Philippine Star 1997.
Lua MLA (9ú heag.)Brown, Tim. "What Is Earth Day?" Philippine Star, 1997.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.