MLA

Elstob, Elizabeth, 1683-1756. The rudiments of grammar for the English-Saxon tongue : first given in English: with an apology for the study of northern antiquities. Being very useful towards the understanding our ancient English poets, and other writers / By Elizabeth Elstob .... 1715. https://collections.library.yale.edu/catalog/15812696.

APA, 6th edition

Elstob, Elizabeth, 1683-1756. (1715)[The rudiments of grammar for the English-Saxon tongue : first given in English: with an apology for the study of northern antiquities. Being very useful towards the understanding our ancient English poets, and other writers / By Elizabeth Elstob ...]. https://collections.library.yale.edu/catalog/15812696.