Vimalaprabha
The Vimalaprabha (Tib. དྲི་མེད་འོད་, Wyl. dri med 'od), translated as Stainless Light or Immaculate Light, is the main commentary on the Kalachakra tantra. Composed by Pundarika, the second Kalkin king of Shambhala, and introduced in Tibet in the 11th century, it is the basis for all Kalachakra commentaries.