TY JOUR TI MHD waves at the pre-front of interplanetary shocks on September 6 and 7, 2017 KW interplanetary magnetic field KW solar wind KW MHD waves KW interplanetary shock KW geomagnetic storm KW cosmic rays KW Forbush decrease JO Solar-Terrestrial Physics AU Starodubtsev, S.A. AU Shadrina, L.P. PY 2024 IS 10 PB INFRA-M Academic Publishing LLC.