Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Meridiankreis-Beobachtungen von Planeten und des Cometen VI. 1863 angestellt an der Sternwarte in Leiden von den Herren Observatoren Dr. NM Kam und A. van Hennekeler. Mitgetheilt von Herrn Director, Prof. F. Kaiser