Initial fol. is fol. no. 93. I see on scan p. 15, the 61st chapter's colophon with the title: Nges par brjod pa'i rgyud bla ma'i bla ma. That means Abhidhānottaratantra (Mngon par brjod pa'i rgyud bla ma), Tôh. no. 369. The final fol. present here is marked 121, but some final pages are missing. (Dan Martin's Hurried Notes)