TY - JOUR AU - Henri Berestycki AU - François Hamel AU - Nikolai Nadirashvili TI - The speed of propagation for KPP type problems. I: Periodic framework JO - Journal of the European Mathematical Society PY - 2005 SP - 173 EP - 213 VL - 7 IS - 2 PB - mathdoc UR - http://geodesic.mathdoc.fr/articles/10.4171/jems/26/ DO - 10.4171/jems/26 ID - JEMS_2005_7_2_a1 ER -