Research Project on Economical Apartment Design, 1930: Ia, Ib, IIb, IIIb: plans

Colored crayons on paper

Red marker on paper

Black ink, partly over graphite, on cream laid paper.

Black marker on paper

Black crayon on paper

Graphite on paper

Red and black marker and blue ink on paper

Graphite on paper

Silverpoint

Graphite on paper

Graphite on paper

Black and green marker and black pen on paper