TY - JOUR AU - Benedikt, Jiří TI - Estimates of the principal eigenvalue of the $p$-Laplacian and the $p$-biharmonic operator JO - Mathematica Bohemica PY - 2015 SP - 215 EP - 222 VL - 140 IS - 2 PB - mathdoc UR - http://geodesic.mathdoc.fr/articles/10.21136/MB.2015.144327/ DO - 10.21136/MB.2015.144327 LA - en ID - 10_21136_MB_2015_144327 ER -