Frequency measurement of the 2S-12D transitions in hydrogen and deuterium, new determination of the Rydberg constant. - Catherine Schwob; Leszek Jozefowski; Ouali Acef; Laurent Hilico; Beatrice de Beauvoir; Francois Nez; Lucile Julien; André Clairon; Francois Biraben (IEEE Trans. Instrum. Meas., 1999)