1. Fight Like the Devil: The First Day at Gettysburg, July 1, 1863 by Chris Mackowski and Daniel T. Davis (Savas Beatie, 2015).
The newest Emerging Civil War series volume.
2. Surveillance and Spies in the Civil War: Exposing Confederate Conspiracies in America's Heartland by Stephen E. Towne (Ohio UP, 2015).
This book explores the cooperative efforts of state and federal government agents to uncover plots against the Union war effort. "Starting in 1862, army commanders took it upon themselves to initiate investigations of antiwar sentiment in those states. By 1863, several of them had established intelligence operations staffed by hired civilian detectives and by soldiers detailed from their units to chase down deserters and draft dodgers, to maintain surveillance on suspected persons and groups, and to investigate organized resistance to the draft. By 1864, these spies had infiltrated secret organizations that, sometimes in collaboration with Confederate rebels, aimed to subvert the war effort. ... Stephen E. Towne is the first to thoroughly explore the role and impact of Union spies against Confederate plots in the North." Among other sources, the bibliography suggests significant archival and newspaper research.