Helgesen, M., & Brown, S. (1999). Active listening: Building skills for understanding : Level 2 [Đĩa CD-ROM]. Cambridge: Cambridge University Press.
Dyfyniad Arddull ChicagoHelgesen, Marc, và Steven Brown. Active Listening: Building Skills for Understanding : Level 2 [Đĩa CD-ROM]. Cambridge: Cambridge University Press, 1999.
Dyfyniad MLAHelgesen, Marc, và Steven Brown. Active Listening: Building Skills for Understanding : Level 2 [Đĩa CD-ROM]. Cambridge: Cambridge University Press, 1999.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.