Cita APA (7th ed.)

ASHLEY RUTH. (1984). USING STRUCTURED COBOL,COBOL-2. WILEY EASTERN LTD.

Cita Chicago (17th ed.)

ASHLEY RUTH. USING STRUCTURED COBOL,COBOL-2. SINGAPORE: WILEY EASTERN LTD, 1984.

Cita MLA (9th ed.)

ASHLEY RUTH. USING STRUCTURED COBOL,COBOL-2. WILEY EASTERN LTD, 1984.