The seasonal unit roots in demographic time series and the possibilities of its exact testing

The seasonal unit roots in demographic time series and the possibilities of its exact testing / Ondřej Šimpach, Petra Dotlačilová .
In: Hradec Ekonomic Days 2013 [549 s.]. ISBN 978-80-7435-251-5 (brož.) Hradecké ekonomické dny 2013. Hradec Králové : Gaudeamus, 2013. S. 426-432 . http://fim2.uhk.cz/hed/data/proceedings_2013_3.pdf .