Aitke, R. (1992). Teaching tenses. Thomas Nelson and Sons.
Cita Chicago Style (17a ed.)Aitke, Rosemary. Teaching Tenses. Edinburgh: Thomas Nelson and Sons, 1992.
Cita MLA (9a ed.)Aitke, Rosemary. Teaching Tenses. Thomas Nelson and Sons, 1992.
Precaución: Estas citas no son 100% exactas.