@PhdthesisMisc{J74_951,
author = {Johannes N\"otzli},
title = {Variationsgleichungen der Keplerbewegung in regularisierten Koordinaten},
note = {Dis_no 5357, Prof. Dr. Eduard Stiefel},
school = {ETH Z{\"u}rich},
doi = {http://dx.doi.org/10.3929/ethz-a-000086402},
year = {1974}
}