Cita APA (7th ed.)

Hull, C. H., & Nie, N. H. (1981). SPSS update 7 - 9: New procedures and facilities for releases 7 - 9. McGraw-Hill.

Cita Chicago (17th ed.)

Hull, C. Hadlai, i Norman H. Nie. SPSS Update 7 - 9: New Procedures and Facilities for Releases 7 - 9. Nueva York: McGraw-Hill, 1981.

Cita MLA (9th ed.)

Hull, C. Hadlai, i Norman H. Nie. SPSS Update 7 - 9: New Procedures and Facilities for Releases 7 - 9. McGraw-Hill, 1981.