Keith, A. L. “Nicholas Yager and Descendants.” The William and Mary Quarterly, vol. 9, no. 3, 1929, pp. 186–200. JSTOR, https://doi.org/10.2307/1921300.
Indicates that Adam Yager married Susanna Kobler (currently listed as disputed in her About me section) in October of 1727. Copies of the JSTOR preview image of this article has been uploaded into the Media tab as a document, one has been edited to highlight the section that indicates this.
Note: Kobler is sometime indicated as Kabler instead. Her father's full name was Frederick Michael Kabler and is more commonly referred to as Frederick in the Germanna immigrant records.