Soars, J., & Soars, L. (1988). Headway - Upper-intermediate: Student's book. Oxford: Oxford University Press.
シカゴスタイル引用形Soars, John, , Liz Soars. Headway - Upper-intermediate: Student's Book. Oxford: Oxford University Press, 1988.
MLA引用形式Soars, John, , Liz Soars. Headway - Upper-intermediate: Student's Book. Oxford: Oxford University Press, 1988.
警告: この引用は必ずしも正確ではありません.