Cita APA (7a ed.)

Ray, G. F. (1988). The diffusion of innovations: An update. [s.n.].

Cita Chicago Style (17a ed.)

Ray, George F. The Diffusion of Innovations: An Update. [S.l.]: [s.n.], 1988.

Cita MLA (9a ed.)

Ray, George F. The Diffusion of Innovations: An Update. [s.n.], 1988.