Cita APA (7a ed.)

Janson, M., & Opitz, H. (2013). World guide to special libraries 2013 (9th ed.). De Gruyter Saur.

Cita Chicago Style (17a ed.)

Janson, Marlies, y Helmut Opitz. World Guide to Special Libraries 2013. 9th ed. [Berlin]: De Gruyter Saur, 2013.

Cita MLA (9a ed.)

Janson, Marlies, y Helmut Opitz. World Guide to Special Libraries 2013. 9th ed. De Gruyter Saur, 2013.