Newman JE, Garces A, Mazariegos M, Michael Hambidge K, Manasyan A, Tshefu A, Lokangaka A, Sami N, Carlo WA, Bose CL, Pasha O, Goco N, Chomba E, Goldenberg RL, Wright LL, Koso-Thomas M, Krebs NF. Theory-driven process evaluation of a complementary feeding trial in four countries. Health Educ Res. 2014 Apr; 29(2):297-305.