Martin HD28 Vintage acoustic guitar samples (MartinGM2_*.wav), recorded and
released by Jeff Learman as part of the Discord SFZ GM Bank, instrument 026
"Acoustic Guitar (steel)". Source: https://github.com/kinwie/Discord-SFZ-GM-Bank
pinned revision 05d5ed8befa042fd9d99a6d159dfc3673d3f8edc.
The instrument's .sfz header states: "License: Creative Commons CC0".

CC0 1.0 Universal (Public Domain Dedication):
https://creativecommons.org/publicdomain/zero/1.0/legalcode
The person who associated a work with this deed has dedicated the work to the
public domain by waiving all of his or her rights to the work worldwide under
copyright law, including all related and neighboring rights, to the extent
allowed by law. You can copy, modify, distribute and perform the work, even for
commercial purposes, all without asking permission.

Used in Open-XY kit 016 "Guitar" (machines/guitar), trimmed, retuned per note,
resampled and re-encoded by tools/kit016_guitar.py. Credit (not required):
Jeff Learman, Martin HD28 samples, Discord SFZ GM Bank.