First, here's a link to Mt. Zion Cemetery:
http://www.findagrave.com/cgi-bin/fg.cgi?page=cr&CRid=45...;
I think I found a marriage notice for William but they printed his last name as "Kurtz" instead of "Martz":
"Married: On the 15th inst., at the Lutheran Parsonage by Rev. Henry Seifert, Mr. William H. Kurtz and Miss Sarah Zacharias, both of Hamilton township, Monroe county, Pa."
The Monroe Democrat, Stroudsburg, Pa., Thursday, August 27th, 1863; Page 3, column 1.