Ebert, K.H. & Hoekstra, J. (1996). 'The progressive in West Frisian and North Frisian - similarities and areal differences'. In: M. Barnes, H. Anderson, E.H. Antonson e.a. (eds.), A Frisian and Germanic Miscellany. Published in honour of Nols Århammar on his sixty-fifth birthday, 7 August 1996. Odense: Odense University Press. 81-101.

rechterperiferie, volgordevariatie, te-plaatsing
rechterperiferie, vormvariatie, te-infinitieven