Khenpo Tsultrim and Thrangu Rinpoche spent many years together teaching members of the Kagyu and Nyingma lineages.

This PDF is a collection of his teachings of 40 pages on the Vajrayogini Practice. 

Vajrayogini one of the higher Tibetan Buddhist practices and should not be practiced without at least receiving the reading transmission of this practice.

This website also has a PDF of Thrangu Rinpoche's teachings on Vajrayogini from a slight different view point.

This website also has a PDF of Elizabeth's 500 page book on all aspects of Vajrayogini.