@misc{weko_30623_1,
   author	 = "北本,俊二 and 常深,博 and 宮本,重徳 and Roussel-Dupre,Diane",
   title	 = "The Unstable Long Term Periodicity of Aql X-1",
   month	 = "aug",
   year 	 = "1992"
}