Retrograde Planets by Grace Inglis
One of the finest book on retrogression of planets under guidance of Manik Chand Jain including lots of original research
Retrograde Planets: Traversing the Inner Landscape by Erin Sullivan
Hindu Dasa System by Grace Inglis
Vakri Planets (Retrograde Planets) by M Subba Rao
Burn Rates: Retrogrades in Astrology – Retrograde Planets by Michael Erlewine
Karmic Astrology: (Volume II) Retrograde Planets and Reincarnation by Martin Schulman
Mystery Of Retrograde Planets by M G Kastwar
Retrograde Planets by Raj Kumar
Retrograde Planets (Part 1 -Jupiter and Venus) by Himanshu Shangari
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