I think this is it!! Novotna M, Havlicek J, Smith AP, Kolbekova P, Skallova A, Klose A, Gasova Z, Pisacka M, Sechovska M, Flegr J (2008). "Toxoplasma and reaction time: Role of toxoplasmosis in the origin, preservation and geographical distribution of Rh blood group polymorphism" Still trying to figure out a question to post.