As part of Thayer Public Library’s One Braintree, One Book initiative, author Shelley Sommerwill visit the library on July 31. The author of the teen book “Hammerin’ Hank Greenberg,” Sommer will be discussing Greenberg, one of the nation’s most famous Jewish athletes. According to library director Terri Stano, Sommer had to do a lot of research into historical records for her book, and will discuss the methods and process of uncovering the facts during her presentation. The event will be held at 6 p.m. in Logan Auditorium.