A Method of Syntax-Checking ALGOL 60
A syntax checker was designed based on the syntax
of ALGOL as described in the ALGOL 60 Report 
[Communications of the ACM, May, 1960].  Since the definition
of the elements of the language is recursive 
it seemed most desirable to design the syntax checker
as a set of mutually recursive processors tied 
together by subroutines which perform certain bookkeeping
functions.  Because of the recursive nature 
of the language and of the syntax checker the problem
of recovery after an error required much attention. 
 A method was devised which permits most programs
to be checked completely despite errors.
CACM August, 1964
Lietzke, M. P.
