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Lua i Stíl Chicago (17ú heag.)Cowen, P., M. Parry-Billings, agus E. Newsholme. Decreased Plasma Tryptophan Levels in Major Depression. 1989.
Lua MLA (9ú heag.)Cowen, P., et al. Decreased Plasma Tryptophan Levels in Major Depression. 1989.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.