Description des installations du service de l'heure
By: par H. Philippot & E. Delporte.
Contributors: Philippot, Hector, 1872-; Delporte, Eugène, 1882-
Publisher: Hayez, imprimeur
Published: 1912
Place of publication: Bruxelles
Language: fre
Number of pages: 73
Subjects: Time.
Notes: At head of title: Observatoire royal de Belgique. Service astronomique.