Koldas allegedly is the name of a planet in a parallel or anti-matter universe. Its inhabitants are referred to as the Koldasians.

LOCATION: 'Antimatter Universe' / Parallel Universe

PHENOTYPE: standard human looking: A1, meaning indistinguishable from Earth humans.

CASE: In 1960, at the age of 16, Edwin from Pinetown, one of the suburbs of Durban, South Africa, discovered that his colleague George, actually was an extraterrestrial, named Valdar, from the planet Koldas.
The case involves direct physical contacts for 2 years while Valdar was on Earth; as well as radio contacts, followed by telepathic contacts later on, since then.

This case was Investigated by Carl van Vlierden, the late Cynthia Hind, Wendelle Stevens,...

According to Branton, the Koldasians are a humanoid species, but -just like the Dal- they are not from within this Universe. Still, they would be members of, or at least have very close ties with the Federation of Planets. Branton also claims the Japanese government has contact with them. (Dreamland & Dulce 30). - Closer examination of the original texts, however, make it clear that the Federation Valdar spoke about is NOT the same Federation of Planets, but a similar organization in their parallel universe.

There are a number of sources with regard to this case.

More information is available at http://galactic.no/rune/koldaskonc.html