Chanting Books are a very integral partly buddhist dharma practice. Great scriptures are written in the compiled sheet of paper where the monks and follower chant the mantra of the various gurus as a discipline and to gain the powerful knowledge of the sutra.
These mantra books are still being used as a daily practice in the monastery.
These book contain mantra of various deities, which the monks chant every day as to get the empowerment from the gods.