@techreport {TR-1989-016,
   type = {Technical Report},
   author = {Andrzej Proskurowski, Maciej M. Syslo },
   title = {Efficient Computations in Tree-Like Graphs },
   institution = {University of Oregon, Computer and Information Sciences Department},
   number = TR-1989-016,
   month = 10,
   year = 1989,
   note = {Available at \url{https://www.cs.uoregon.edu/Reports/TR-1989-016.pdf}},
}