LISP implementations on small machines

[Mark Kahrs]

The first implementation was done for the 7090 by McCarthy (hence CAR and
CDR --- Contents of Address Register and Contents of Decrement Register).

If you want to see a tiny implementation then look for the PDP-1
implementation done by L Peter Deutsch.  There's a book chapter and then I
found this report:

http://s3data.computerhistory.org/pdp-1/DEC.pdp_1.1964.102650371.pdf