[1970s] Jan Dibbets and Ger van Elk (1) Jan Dibbets, Roodborst territorium/Sculptuur 1969, Robin Redbreast's Territory/Sculpture 1969, Domaine d'un rouge-gorge/Sculpture 1969, Rotkehlchenterritorium/Skulptur 1969. New York, Seth Siegelaub, 1970. Softcover, 18 x 12 cm, 32 pp. First edition. Classic artists' book by the Dutch Conceptual artist. Features photographs, topographical surveys, and handwritten notes translated into English, French and German. The book documents a 1969 installation in the Vondelpark in Amsterdam in which Dibbets tried to extend the natural territory of a robin, by placing poles for the bird to perch on. Very good copy, rare. (2) Ger van Elk, Art & Project booklet featuring documentation of five works, among them 'The Well Shaven Cactus' (1969) and 'The Discovery of the Sardines' (1971). First printing April 1972, edition of 300. Staple bound, 21 x 10 cm, 18 pp. Slight toning on exterior edges, moderate creasing along top and bottom of covers, otherwise good. (total 2)