Kawakami K, Kawakami F, Tomonaga M, Kishimoto T, Minami T, Takai-Kawakami K (2011) 
Origins of a theory of mind.

Infant Behavior & Development, 34, 264-269

Kawakami K, Takai-Kawakami K, Kawakami F, Tomonaga M, Suzuki M, Shimizu Y (2008) 
Roots of smile: A preterm neonates' study.

Infant Behavior and Developme, 31:518-522