TY  - JOUR
TI  - Preface by the editor of the issue
JO  - Žurnal Sibirskogo federalʹnogo universiteta. Matematika i fizika
PY  - 2021
SP  - 677
EP  - 678
VL  - 14
IS  - 6
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/JSFU_2021_14_6_a0/
LA  - en
ID  - JSFU_2021_14_6_a0
ER  -