signed lower right in graphite numbered P.A. lower left in graphite titled center verso in graphite provenance: from the Grace Hertlein Collection and Archives The portfolio was commissioned by Systems Dimensions Limited, an early Canadian computer services firm, in 1973 as a way of promoting computers not only as a tool to expand industrial and […]

signed lower left in graphite signed, titled, and dated lower right verso in blue ink provenance: from the Grace Hertlein Collection and Archives

signed lower right in graphite dated and numbered 24/25 lower left in graphite signed and titled center verso in brown ink stamped with A.R.T.A stop center verso in black ink provenance: from the Grace Hertlein Collection and Archives

signed lower right in graphite dated and numbered 24/25 lower left in graphite signed and titled center verso in brown ink stamped with A.R.T.A stop center verso in black ink provenance: from the Grace Hertlein Collection and Archives

signed, titled illegibly, and dated lower left in graphite numbered 7/7, 14/15, and 28/105 lower right in graphite provenance: from the Grace Hertlein Collection and Archives

signed, titled illegibly, and dated lower left in graphite numbered 2/7, 14/15, and 93/105 lower right in graphite provenance: from the Grace Hertlein Collection and Archives

signed lower right in blue ink provenance: from the Grace Hertlein Collection and Archives

signed and titled center verso in blue ink stamped with A.R.T.A stop center verso in black ink provenance: from the Grace Hertlein Collection and Archives

signed lower right by both artists in graphite dated and numbered 13/33 lower left in graphite signed by both artists and titled center verso in brown ink stamped with A.R.T.A stop center verso in black ink provenance: from the Grace Hertlein Collection and Archives

signed and dated lower right with in the image in graphite numbered 11/50 lower left within the image in graphite provenance: from the Grace Hertlein Collection and Archives

signed and dated lower right in graphite numbered E.A lower left in graphite provenance: from the Grace Hertlein Collection and Archives

signed and dated lower right in graphite numbered E.A lower left in graphite provenance: from the Grace Hertlein Collection and Archives