Não informado. (1957). Abstracts of Bulgarian Scientific Literature. Centre of Scientific Information and Documentation.
Lua i Stíl Chicago (17ú heag.)Não informado. Abstracts of Bulgarian Scientific Literature. Sofia: Centre of Scientific Information and Documentation, 1957.
Lua MLA (8ú heag.)Não informado. Abstracts of Bulgarian Scientific Literature. Centre of Scientific Information and Documentation, 1957.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.