Bjelland, H. (1992). Using online scientific & engineering databases. Windcrest.
Lua i Stíl Chicago (17ú heag.)Bjelland, Harley. Using Online Scientific & Engineering Databases. Blue Ridge Summit, PA: Windcrest, 1992.
Lua MLA (8ú heag.)Bjelland, Harley. Using Online Scientific & Engineering Databases. Windcrest, 1992.
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