Anna Bella Geiger, Mapas elementares no. 1 , 1976. Black and white video, single channel, sound. Duration: 2 min. 48 sec. Edition 5 +2AP. (Film still).

Luis Arias Vera. Sobre Aereo N.66 , 1968. Mixed media on linen 45 1/3 x 68 7/8 in. (115 x 175 cm)

Luis Arias Vera. Sobre Aereo N.81 , 1968-2014. Mixed media over linen. 43 1/4 x 66 7/8 in. (110 x 170 cm)

Sigfredo Chacón. CARTA , 1974. From the London Drawings Series. Acrylic, collage and graphite on paper. 25 x 20 1/2 in. (63.5 x 52.1 cm)

Eugenio Dittborn. We (A Text Written by Eugenio Dittborn on the Occasion of the XII Paris Biennale) , 1983. Acrylic and ink on paper. from the series Airmail Paintings . 68 1/2 x 56 7/8 in. (174 x 144.5 cm)

Anna Bella Geiger, Carta a un amigo , 1974. Wax and marker on embossed silver paper. 8 x 8 15/16 in. (20.3 x 22.7 cm)

Anna Bella Geiger, Carta a un amigo , 1974. Wax on gelatin silver print. 7 1/4 x 9 1/2 in. (18.4 x 24.1 cm)

Sigfredo Chacón. Air Mail , 1974. Oil pastel and graphite on paper. from the London Drawing Series, 1974 . 15 1/2 x 11 in. (39.4 x 27.9 cm)

Sigfredo Chacón. Expreso Internacional , 1974. Ink, graphite and mixed media on paper. from the London Drawing Series, 1974 . 15 1/2 x 11 in. (39.4 x 27.9 cm)

Sigfredo Chacón. Air Mail Envelope , 1974. Collage, paper, graphite and acrylic paint. from the London Drawing Series, 1974 . 15 1/2 x 11 in. (39.4 x 27.9 cm)

Mirtha Dermisache. Untitled , 1975 . Chinese ink on onionskin. 11 5/8 x 8 1/4 in. (29.5 x 21 cm)

Emilia Azcárate. Untitled , 2013. Typewriter ink on Arches postcard. from the series Postales . 4 1/8 x 6 1/16 in. (10.5 x 15.5 cm). front

Emilia Azcárate. Untitled , 2013. Typewriter ink on Arches postcard. from the series Postales . 4 1/8 x 6 1/16 in. (10.5 x 15.5 cm). reverse

Emilia Azcárate. Untitled , 2013. Watercolor on Arches postcard. from the series Postales . 4 1/8 x 6 1/16 in. (10.5 x 15.5 cm). front

Emilia Azcárate. Untitled , 2013. Watercolor on Arches postcard. from the series Postales . 4 1/8 x 6 1/16 in. (10.5 x 15.5 cm). reverse

Horacio Zabala. Censurar , 1974. Leaflet map with an inked rubber stamp mark inside of an envelope. 5 1/2 x 8 5/8 in. (14 x 22 cm)

Horacio Zabala. Today, Art is a Prison , 1976. Postcard. 4 1/8 x 5 7/8 in. (10.5 x 15 cm)

Humberto Marquez. Helicoptero , 1968. Lithograph on sticker paper. 9 3/8 x 8 5/8 in. (24 x 22 cm). Edition of 30

Clemente Padin. Correo del Sur (Southern Post) Nº 1 , 2000. Stamps on paper. 8 x 5 3/8 in. (20.5 x 13.8 cm)

Humberto Marquez. Policias y estudiante , 1968. Lithograph on sticker paper. 9 3/8 x 8 5/8 in. (24 x 22 cm). Edition of 30

Humberto Marquez. Presidente , 1968. Lithograph on sticker paper. 9 3/8 x 8 5/8 in. (24 x 22 cm). Edition of 30

Liliana Porter. Mail Exhibition #3 - To Be Wrinkled and Thrown Away , 1969 Offset print with rubber stamping.

Liliana Porter. Mail Exhibition #2 - Shadow For a Glass , 1969. Offset print with rubber stamping.

Guillermo Deisler. Contemporáneo, Postcard. 5 7/8 x 4 1/8 in. (15 x 10.5 cm). front

Guillermo Deisler. Contemporáneo , Postcard. 5 7/8 x 4 1/8 in. (15 x 10.5 cm). reverse

Guillermo Deisler Memorize , 1980’s, Postcard. 5 7/8 x 4 1/8 in. (15 x 10.5 cm). front

Guillermo Deisler Memorize , 1980’s, Postcard. 5 7/8 x 4 1/8 in. (15 x 10.5 cm). reverse

Guillermo Deisler. Brief (15.1.1991) , 1991. Postcard. 5 3/4 x 4 1/8 in. (14.8 x 10.5 cm). front

Guillermo Deisler. Brief (15.1.1991) , 1991. Postcard5 3/4 x 4 1/8 in. (14.8 x 10.5 cm). reverse

Guillermo Deisler. Poema Visual , Postcard. 5 7/8 x 3 7/8 in. (15 x 10 cm). front

Guillermo Deisler. Poema Visual , Postcard. 5 7/8 x 3 7/8 in. (15 x 10 cm). reverse

Eduardo Antonio Vigo. Discurso , 1993. Mixed media. Offset print, stamp and seal on cardboard. 4 1/4 x 6 5/8 in. (11 x 17 cm)

Eduardo Antonio Vigo. Autobiografía , 1996. Mixed media. Offset print, stamp and seal on cardboard. 4 1/4 x 6 5/8 in. (11 x 17 cm). front

Eduardo Antonio Vigo. Autobiografía , 1996. Mixed media. Offset print, stamp and seal on cardboard. 4 1/4 x 6 5/8 in. (11 x 17 cm). reverse

Eduardo Antonio Vigo. Tango , 1994. Mixed media. Offset print, stamp and seal on cardboard. 4 1/4 x 6 5/8 in. (11 x 17 cm). front

Eduardo Antonio Vigo. Tango , 1994. Mixed media. Offset print, stamp and seal on cardboard. 4 1/4 x 6 5/8 in. (11 x 17 cm). reverse

Eduardo Antonio Vigo. Ultima Exposición Internacional de Arte Correo’75 , 1975. 1 x 9 3/4 in. (2.5 x 25 cm)

Eduardo Antonio Vigo. Set Free Palomo , 1986. Stamps. 7 1/8 x 4 1/4 in. (18.4 x 11 cm)

Graciela Sacco. Serie Bocanada , 1994. Stamp and ink on paper. 12 1/8 x 8 1/4 in. (31 x 21 cm)

Diego Barboza. Buzón de arte , 1976. Offset print. Año 1 Número 1. 29 x 21 1/2 in. (73.7 x 54.6 cm). front

Diego Barboza. Buzón de arte , 1976. Offset print. Año 1 Número 1. 29 x 21 1/2 in. (73.7 x 54.6 cm). reverse

Diego Barboza. Buzón de arte , 1976. Offset print. Año 1 Número 2. 29 x 21 1/2 in. (73.7 x 54.6 cm). front

Diego Barboza. Buzón de arte , 1976. Offset print. Año 1 Número 2. 29 x 21 1/2 in. (73.7 x 54.6 cm). reverse

Luis Aria Vera. Estampilla No. 40 , 1968. Mixed media on board. 31 5/8 x 24 in. (80.5 x 61 cm)

Paulo Bruscky, PostAçao , 1975. Slide documentation of a performance.

Paulo Bruscky. Untitled , Unknown. Serigraph. 12 x 8 in. (30.5 x 20.3 cm)

Paulo Bruscky. Untitled .

Paulo Bruscky. Untitled . 4 5/8 x 6 3/8 in. (12 x 16.5 cm). front

Paulo Bruscky. Untitled . 4 5/8 x 6 3/8 in. (12 x 16.5 cm). reverse

Paulo Bruscky. Untitled .

Paulo Bruscky. Unknown , 1977. Print. 9 x 6 1/2 in. (22.9 x 16.5 cm)

Paulo Bruscky. Unknown . Collage on paper. 8 1/2 x 12 in. (21.6 x 30.5 cm)

Paulo Bruscky. Presépio Urbano , 1987-1988. Postcard. 5 7/8 x 8 in. (15 x 20.5 cm) front

Paulo Bruscky. Presépio Urbano , 1987-1988. Postcard. 5 7/8 x 8 in. (15 x 20.5 cm) reverse

Clemente Padin. Correo del Sur (Southern Post) Nº 2 , 2000. Stamps on paper. 8 3/8 x 5 1/2 in. (21.5 x 14 cm)

Eduardo Kac. 2x3X , 1982. Electrostatic monoprint on paper. 8 1/2 x 10 3/8 in. (21.6 x 26.5 cm)

Eduardo Kac. Tilt , 1982. Electrostatic monoprint on paper. 8 1/2 x 9 3/4 in. (21.6 x 24.8 cm)