APA Citation

Portoviejo Guachún, X. A. (2017). Audio material for improving essential level B1 conversations according to the common European framework.

Chicago Style Citation

Portoviejo Guachún, Xavier Alejandro. Audio Material for Improving Essential Level B1 Conversations According to the Common European Framework. 2017.

MLA Citation

Portoviejo Guachún, Xavier Alejandro. Audio Material for Improving Essential Level B1 Conversations According to the Common European Framework. 2017.

Warning: These citations may not always be 100% accurate.