There is the very beautiful compilation of the letters Shri Nathji wrote to his devotees over the years. The compilation is in a handwritten register and was done by the late Shri K.R. Narsikar of Nagpur, Maharashtra. It had later, in 1987, been brought over to Delhi and given to Shri Nathji by Ujwala Narsikar, the daughter of Shri Narsikar, after Shri Narsikar had passed away.