@techreport {TR-1988-005,
   type = {Technical Report},
   author = {John Anderson, Arthur Farley},
   title = {Plan Abstraction Based On Operator Generalization},
   institution = {University of Oregon, Computer and Information Sciences Department},
   number = TR-1988-005,
   month = 4,
   year = 1988,
   note = {Available at \url{https://www.cs.uoregon.edu/Reports/TR-1988-005.pdf}},
}