Another useful volume is Hemrāj Śākya's Nepāla-lipi-prakāśa (Kathmandu: Nepāla Rājakīya Prajñā
Pratiṣṭhāna, Vikram Saṃvat 2030 [=1974]).
The Hathi Trust record is here:
http://catalog.hathitrust.org/Record/007872735
good luck!
Matthew Kapstein
Directeur
d'études,
Ecole Pratique des Hautes Etudes
Numata Visiting Professor of Buddhist Studies,
The University of Chicago