@PhdthesisMisc{N75_959,
author = {Niklaus Sigrist},
title = {Investigation of hamiltonian systems with resonances and geometrical singularities},
note = {Dis_no 5429, Prof. Dr. Eduard Stiefel},
school = {ETH Z{\"u}rich},
doi = {http://dx.doi.org/10.3929/ethz-a-000085824},
year = {1975}
}