1: Part of book covers ballpark legends, using reliable background sources (5)
3: The age of the equal rights amendment (3)
5: Shinny up and start to cut branch (5)
7: What's left when you burn the tree (3)
8: Instrument making snout feel odd (4,5)
11: Sacred oratorio includes statement of belief (5)
12: Neither partner finds way out of country (3)
13: City that cowboys used to avoid (5)