Frank Residence, Pittsburgh, Pennsylvania, 1939-1940: Plumbing diagrams (1/8" = 1'-0")

Black ink and gray wash on cream laid paper; verso: gray wash

Watercolor and white gouache over black and colored chalk on ivory wove paper

Graphite and black chalk on off-white wove paper

Graphite on blue wove paper

Crayon on paper

Brown ink on off-white wove paper

Graphite on off-white wove paper

Black ink over graphite on modern laid paper

Watercolor over graphite on off-white wove paper

Watercolor on cream wove paper

Watercolor and graphite on layered off-white wove paper

Watercolor on off-white wove paper