Solid that has a continuous developable surface with 2 congruent semi circular edges, and 4 vertices that define a square; member of a special family of rollers
solid that has a continuous developable surface with 2 congruent semi circular edges, and 4 vertices that define a square; member of a special family of rollers (en)
геометрическое тело, выпуклая оболочка двух окружностей (ru)