@incollection{compref38,
   author = {Bar-Hillel and Kasher,Y and Shamir,E},
   year = {1967},
   title = {Measures of Syntactic Complexity},
   booktitle = {Machine Translation},
   editor = {Booth,AD},
   publisher = {North-Holland},
   address = {Amsterdam},
   pages = {30-50}
}