Greenpeace, "Save or Delete" poster. Image by Banksy (British, born 1974). Frame: 54.5 x 72.5 cm (21.5 x 28.5 inches)

All lots that do not carry established documented provenance nor any past record of auction history record are described in the catalog as attributed.

All authorship of items in this catalog are described according to the following terms:

By [Artist Name]: In our opinion, the work is by the artist.

Attributed to [Artist Name]: In our opinion, the work may be ascribed to the artist on the basis of style, but there may be some question as to actual authorship.

In the manner of [Artist Name]: In our opinion, the work was executed by an unknown hand, but was designed deliberately to emulate the style of the artist.

After [Artist Name]: In our opinion, the work was executed by an unknown hand, but is a deliberate copy of a known work by the artist.

Circle of [Artist Name]: In our opinion, a work of the period of the artist showing his influence, closely associated with the artist but not necessarily his pupil.

Follower of [Artist Name]: In our opinion, a work by a pupil or a follower of the artist (not necessarily a pupil).

American, 19th century: In our opinion, this work was executed by an unknown hand, and can only be identified by origin (i.e., region, period).

Bears signature: In our opinion, the signature on the artwork may be spurious.

Apocryphal: Of doubtful authenticity.