Dictionnaire Infernal: Volac, great president in the underworld; he appears in the form of a child with angel wings, mounted on a two-headed dragon. He knows the abode of the planets and the retreat of the serpents. Thirty legions obey him.
Pseudomonarchia Daemonum: Volac is a great president, and commeth abroad with angels wings like a boie, riding on a twoheaded dragon, he perfectlie answereth of treasure hidden, and where serpents may be seene, which he delivereth into the conjurors hands, void of anie force or strength, and hath dominion over thirtie legions of divels.
Livre des Esperitz: ...Out of 59 demons thus described in the treatise edited by Wier, 36, i.e. almost two-thirds, are monsters which combine to varying degrees the human, animal and angelic species: a typical example of a combination in this respect is represented by Volac, who has the appearance of a boy with angel wings, riding a two-headed dragon.
Munich Manual of Demonic Magick: Name: Volach. Rank: president. Appearance: boy, with wings of angel; rides on dragon; has two heads. Function: responds about hidden treasures, serpents appear, gives over serpents into the hands of the exorcist. Number of legions: 27.
The Lesser Key of Solomon: VOLAC, or VALAX, or VALU, or UALAC. -- The Sixty-second Spirit is Volac, or Valak, or Valu. He is a President Mighty and Great, and appeareth like a Child with Angel's Wings, riding on a Two-headed Dragon. His Office is to give True Answers of Hidden Treasures, and to tell where Serpents may be seen. The which he will bring unto the Exorciser without any Force or Strength being by him employed. He governeth 38 Legions of Spirits.
Other references:
DEMONOLATOR'S HANDBOOK: I was putting off performing an invocation here, so Volac had sent me a not so subtle sign before I even begun.
Volac felt cold. Like a cold refreshing mist that first originated on my left shoulder, but the deeper I went into meditation, it spread around my body. His voice was very calm. He came as a male voice to me.
First Volac did not want me to communicate on his behalf, or pass any messages. He is more than capable of doing it himself. He also did not ask for preferences when it came to bringing people to him. Whoever has business with Volac's areas of expertise should go and see him themselves and no matter how you're using that area of expertise, he'll deliver. If he likes you as a person and will want to continue working with you long-term, he's capable of telling that to you himself.
For who should seek Volac, well, anyone that is preparing to literally raise snakes or other reptiles, but also those that have figurative snakes in their mist. I had certain business about said figurative snakes myself and Volac was completely fine with taking on that job. He is not able to draw the snakes out, he's able to make fate blow at them hard enough for said snakes to leave your path, so don't be afraid to petition not only for discovery, but also removal of your enemies.
When it comes to finding treasure, this should also be interpreted as "secret windfall". If there is fortune possible in your path, Volac can draw it out and place it right in front of you.
Associations:
NAMES: Valac, Volac, Valak, Valu, Valax, Ualac, Volach
DIRECTION: West
PLANETS: Mercury
METAL: Mercury
ELEMENT: Earth, water
COLOR: Orange
BOTANICALS AND AROMATICS: Sesame, storax
TAROT: Nine of wands
ZODIAC: Sagittarius
DATE: December 3rd to December 12th, night
ANIMAL: Dragon, snake
The Lesser Key of Solomon, pg. 42
Dictionnaire Infernal, pg. 696