Hippel, Eric von, and Georg von Krogh. “Free Revealing and the Private-Collective Model for Innovation Incentives.” R and D Management 36, no. 3 (June 2006): 295–306.
Harhoff, Dietmar, Joachim Henkel, and Eric von Hippel. “Profiting from Voluntary Information Spillovers: How Users Benefit by Freely Revealing Their Innovations” Research Policy 32, no. 10 (December 2003): 1753–69.
Self-determination Theory
Undermining Theory and criticisms