The undulating surfaces of these works push the boundary between sculpture and painting.

The lower plateaus have an undulating surface and an average height of 1300 feet.

They might be slick with ice, but their undulating surface would provide some traction.

The floor is distinguished only by a pair of small craterlets and a slightly undulating surface.

The undulating surface was cold and made his fingers ache.

It has a slightly undulating surface, reaching the 156 meters at its highest point.

Note the exits into 'the wings' at the northern end and how the undulating surfaces create the illusion of a larger space.

A little undulating surface, with a spike that stuck up.

With an undulating surface of generally productive soil, agriculture became the principal occupation.

The first challenge is to place the ball in the proper area on the course's lightning-quick, undulating putting surfaces.