Cita APA (7a ed.)

Gusnidar. (2003). WINDOW ON THE WORLD A New Approach to Learning English for SMU year 1 Semester System. Erlangga.

Cita Chicago Style (17a ed.)

Gusnidar. WINDOW ON THE WORLD A New Approach to Learning English for SMU Year 1 Semester System. Erlangga, 2003.

Cita MLA (8a ed.)

Gusnidar. WINDOW ON THE WORLD A New Approach to Learning English for SMU Year 1 Semester System. Erlangga, 2003.