A few more can be found here with black-and-white overlays:
http://www.dailymail.co.uk/news/article-2219584/Ghosts-war-A...
http://www.mymodernmet.com/profiles/blogs/the-ghosts-of-worl...
http://www.pbs.org/newshour/updates/images-world-war-devasta...
http://www.businessinsider.com.au/europe-overlay-photos-2014...
http://petapixel.com/2013/04/02/photos-of-modern-day-locatio...