Kool, Wouter; Werf, Titia van der & Lavoie, Brian. Preservation Health Check: Monitoring Threats to Digital Repository Content, book, April 2014; (https://digital.library.unt.edu/ark:/67531/metadc463532/m1/1/: accessed November 14, 2018), University of North Texas Libraries, Digital Library, digital.library.unt.edu; .