APA

Method R., . (1977). Do you want to speak Spanish?. Barcelona: Ramón Sopena, S.A.

Chicago

Method Roberston, . 1977. Do you want to speak Spanish?. Barcelona: Ramón Sopena, S.A.

Harvard

Method R., . (1977). Do you want to speak Spanish?. Barcelona: Ramón Sopena, S.A.

MLA

Method Roberston, . Do you want to speak Spanish?. Barcelona: Ramón Sopena, S.A. 1977.