Some other sources might be Janet and Colin Bord's Alien Animals, Jerome Clark's Unexplained!, Robert Trubshaw's Explore Phantom Black Dogs, and Rosemary Guiley's The Encyclopedia of Ghosts and Spirits (Third Edition).
Some other sources might be Janet and Colin Bord's Alien Animals, Jerome Clark's Unexplained!, Robert Trubshaw's Explore Phantom Black Dogs, and Rosemary Guiley's The Encyclopedia of Ghosts and Spirits (Third Edition).