http://humanvarieties.org/2013/05/26/the-onset-and-development-of-b-w-ability-differences-early-infancy-to-age-3-part-1/
 
Infants, as they age, international hierarchies, mixed pops
 
http://www.oecd.org/pisa/
 
http://akarlin.com/2012/08/minorities-cognitive-performance-in-the-uk/
 
https://twitter.com/thealthype/status/806295599712768001
 
Lynn 2006