@article{oai:nagoya.repo.nii.ac.jp:00031245,
 author = {Yamamoto, Toshio and Satio, Akihiko},
 issue = {1},
 journal = {Memoirs of the Faculty of Engineering, Nagoya University},
 month = {Jan},
 note = {In a vibratory system having multiple degree-of-freedom and under parametric excitation of frequency ω, oscillations of “summed and differential types” with frequencies ωi (≒pi), ωj (≒pj) take place, when ω becomes nearly equal to sum of and difference in two natural frequencies pi, pj, i.e., ω= pi±pj = pij, in which pij is the resonant frequency. In the present paper, the characteristics of these oscillations are studied theoretically and experimentally, and it is seen that solutions of first approximation obtained through rather simple analysis grasp sufficiently these oscillatory phenomena. Futhermore, it is cleared up that unstable oscillations can occur only in summed type and not in differential type.},
 pages = {102--117},
 title = {On the oscillations of "Summed and differential types" under the parametric excitation},
 volume = {19},
 year = {1968}
}