European Journal of Mathematics
European Journal of Mathematics > 2018 > 4 > 3 > 859-878
European Journal of Mathematics > 2019 > 5 > 3 > 858-871
European Journal of Mathematics > 2019 > 5 > 4 > 1242-1251
European Journal of Mathematics > 2019 > 5 > 4 > 1139-1155