European convention on the international classification of patents for invention, Dec. 19, 1954
Subtitle: with amended form of annex which entered into force on Dec. 16, 1961.
Series: Treaty series -- no. 12 (1963)
Publisher: H.M.S.O.
Published: 1963
Place of publication: London
Language: eng
Number of pages: 49
Notes: English and French.