Educational Testing Services. (2012). The official guide to the TOEFL test (4th ed.). McGraw-Hill ; Tata McGraw Hill.
Dyfyniad Arddull ChicagoEducational Testing Services. The Official Guide to the TOEFL Test. 4th ed. New York : New Delhi: McGraw-Hill ; Tata McGraw Hill, 2012.
Dyfyniad MLAEducational Testing Services. The Official Guide to the TOEFL Test. 4th ed. McGraw-Hill ; Tata McGraw Hill, 2012.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.