Bertolo, S. (2001). Language acquisition and learnability. Cambridge University.
Chicago-čujuhus (17. p.)Bertolo, Stefano. Language Acquisition and Learnability. Cambridge: Cambridge University, 2001.
MLA-čujuhus (9. p.)Bertolo, Stefano. Language Acquisition and Learnability. Cambridge University, 2001.
Muitte dárkkistit čujuhemiid riektatvuođa, ovdal go geavahat daid iežat deavsttas.