Author,Title,Journal,ISSN,Publisher,Date,Volume,Number,Page,URL,URL(DOI) T. Fukuda and Xinkai Chen and Shuxiang Guo,A VSS disturbance observer and its applications,Proceedings of the 1998 IEEE International Conference on Control Applications (Cat. No.98CH36104),,IEEE,2002-11-27,1,,403-407,https://cir.nii.ac.jp/crid/1874242817714346880,https://doi.org/10.1109/cca.1998.728469