TY - JOUR AU - Došlý, Ondřej AU - Hilscher, Roman TI - Spectral properties of fourth order differential operators JO - Mathematica Bohemica PY - 1997 SP - 153 EP - 168 VL - 122 IS - 2 PB - mathdoc UR - https://geodesic-test.mathdoc.fr/articles/10.21136/MB.1997.125911/ DO - 10.21136/MB.1997.125911 LA - en ID - 10_21136_MB_1997_125911 ER -