TY - JOUR AU - B. Odehnal TI - Isoptic Ruled Surfaces of Developable Surfaces JO - Journal for geometry and graphics PY - 2021 SP - 1 EP - 17 VL - 25 IS - 1 PB - mathdoc UR - http://geodesic.mathdoc.fr/item/JGG_2021_25_1_JGG_2021_25_1_a0/ ID - JGG_2021_25_1_JGG_2021_25_1_a0 ER -