Lit-Hung Leung M.D.
His original paper on this subject was released in 1997. So it's now (2007) only been 10 years since then. This explains somewhat why the power of B5 vitamins for acne prevention is not more well known.
Dr. Leung hypothesized that large doses of Vitamin B5 (Pantothenic Acid) would slow down the overproduction of oil. He then did a real life study and found that this was exactly the case. He found that not only does Vitamin B5 slow down the overproduction of oil and in effect cure acne, it also causes the pores of the skin to shrink making the skin "more beautiful."