APA-viite

Letters Zone. (2017). Practice book LDC with OMR and explanations. Letterzone.

Chicago-tyylinen lähdeviittaus

Letters Zone. Practice Book LDC with OMR and Explanations. Kozhikode: Letterzone, 2017.

MLA-viite

Letters Zone. Practice Book LDC with OMR and Explanations. Letterzone, 2017.