Walters, Daniel and Petty, Mary E. "The Milestones of Science Collection: The Public Library and the Conservation of Cultural Heritage." Libraries & Culture (1999), v. 34 no.3: 262-276 „Archived copy“. 2011-yil 17-iyunda asl nusxadan arxivlangan. Qaraldi: 2008-yil 15-noyabr.
Walters, Daniel and Petty, Mary E. "The Milestones of Science Collection: The Public Library and the Conservation of Cultural Heritage." Libraries & Culture (1999), v. 34 no.3: 262-276 „Archived copy“. 2011-yil 17-iyunda asl nusxadan arxivlangan. Qaraldi: 2008-yil 15-noyabr.