TY - JOUR AU - K. Yu. Kishkis TI - Letter to the editors: ``The index of the Bitsadze--Samarski{\v\i} problem for harmonic functions'' [Differentsial'nye Uravneniya \textbf{24} (1988), no.~1, 105--110; MR0930160] JO - Differencialʹnye uravneniâ PY - 1989 SP - 546 VL - 25 IS - 3 PB - mathdoc UR - http://geodesic.mathdoc.fr/item/DE_1989_25_3_a28/ LA - ru ID - DE_1989_25_3_a28 ER -