In each source file that you've written, place a comment header at the top of the file. [NOTE: The example below uses the comment notation ("#") recognized by most scripting languages (e.g., Bash, Perl, Python, R, Ruby). Adjust that notation accordingly based on the language your code is written in.]
# This file is part of the Minnesota Population Center's {PROJECT TITLE}.
# For copyright and licensing information, see the NOTICE and LICENSE files
# in this project's top-level directory, and also on-line at:
# https://github.com/mnpopcenter/{REPO-NAME}
Replace the placehoders {PROJECT TITLE} and {REPO-NAME}