Answering English questions by Computer: A Survey
Fifteen experimental English language question-answering
systems which are programmed and operating 
are described and reviewed.  The systems range from a conversation
machine to programs which make sentences 
about pictures and systems which translate from English
into logical calculi.  Systems are classified 
as list-structured data-based, graphic data-based, text-based
and inferential.  Principles and methods 
of operations are detailed and discussed.  It is concluded
that the data-base question-answer has passed 
from initial research into the early developmental
phase.  The most difficult and important research 
questions for the advancement of general-purpose language
processors are seen to be concerned with measuring, 
dealing with ambiguities, translating into formal
languages and searching large tree structures.
CACM January, 1965
Simmons, R. F.
