@techreport{weko_62458_1,
   author	 = "Takehiro,Ito and Yuichiro,Miyamoto and Hirotaka,Ono and Hisao,Tamaki and Ryuhei,Uehara",
   title	 = "Graph Orientation Problems for Multiple st-Reachability",
   year 	 = "2009",
   institution	 = "Tohoku University, Sophia University, Kyushu University, Meiji University, Japan Advanced Institute of Science and Technology",
   number	 = "5",
   month	 = "jul"
}