Try these: https://softwarepreservation.computerhistory.org/LISP/lisp15_family.html#Lisp_15_Programmers_Manual_ https://softwarepreservation.computerhistory.or

Try these: https://softwarepreservation.computerhistory.org/LISP/lisp15_family.html#Lisp_15_Programmers_Manual_ https://softwarepreservation.computerhistory.org/LISP/lisp15... https://softwarepreservation.computerhistory.org/LISP/lisp15_family.html#LISP_15_Primer_ https://softwarepreservation.computerhistory.org/LISP/lisp15... https://softwarepreservation.computerhistory.org/LISP/lisp15_family.html#Berkeley_and_Bobrow_ https://softwarepreservation.computerhistory.org/LISP/lisp15... (The third one includes the source code to PDP-1 Lisp.)