J. Hidrografo A. J. Monteiro de Barros Luis de Oliveira Use of Raydist System in Portuguese Guinea Survey PDF (English)
J. Th. Verstelle An Evaluation of the Accuracy of Decca as a Means of Distance Measuring over Land PDF (English)
André Gougenheim Latitude and Azimuth Determination by the Observation of a Single Unknown Star PDF (English)
Alfred H. Kerrick Precise Astronomic Positions from projected Star Positions analytically processed PDF (English)
H. L. G. Bencker Construction of Plotting Sheets of General Bathymetric Chart of the Oceans PDF (English)
