The Philadelphia Museum of Art has an unusually strong collection of works on paper by Paul Klee. Robert Wolterstorff, a National Endowment for the Arts curatorial intern in the Prints, Drawings, and Photographs department, assembled 53 works on paper from the permanent collection at the Museum and local private collections in the Philadelphia area for an exhibition that explores Klee's experiments with line, tonality, and color. Wolterstorff worked under the supervision of Ann Percy.