-
P. Kowalski
http://www.imp.gda.pl/fileadmin/files/transactions/141/paper1_141_2018_.pdf/No. 141, 2018, 3-30
-
R. Matysko
http://www.imp.gda.pl/fileadmin/files/transactions/141/paper2_141_2018_.pdf/No. 141, 2018, 31-40
-
P. Lampart
http://www.imp.gda.pl/files/transactions/141/paper3_141_2018_.pdf/No. 141, 2018, 41-52