References:
Quantum Chromodynamics - Wikipedia
https://en.wikipedia.org/wiki/Quantum_chromodynamics
Strong CP (charge-parity) Problem - Wikipedia
https://en.wikipedia.org/wiki/Strong_CP_problem
Quark - Wikipedia
https://en.wikipedia.org/wiki/Quark
Origin of the Word “Quark” - ScienceFriday
https://www.sciencefriday.com/articles/the-origin-of-the-word-quark/
Eightfold Way (Physics) - Wikipedia
https://en.wikipedia.org/wiki/Eightfold_way_(physics)
Color Charge - Wikipedia
https://en.wikipedia.org/wiki/Color_charge
Non-Abelian Gauge Theory - Wikipedia
https://en.wikipedia.org/wiki/Non-abelian_gauge_theory
Lagrangian Function - Britannica
https://www.britannica.com/science/Lagrangian-function
Yang-Mills Theory - Wikipedia
https://en.wikipedia.org/wiki/Yang%E2%80%93Mills_theory
Special Unitary Triplet - Wikipedia
https://en.wikipedia.org/wiki/Special_unitary_group#The_group_SU(3)
Asymptotic Freedom - Wikipedia
https://en.wikipedia.org/wiki/Asymptotic_freedom
Color Confinement - Wikipedia
https://en.wikipedia.org/wiki/Color_confinement
Direct Photon Production - Wikipedia
https://en.wikipedia.org/wiki/Direct_photons
Jet (Physics) and Hadronization - Wikipedia
https://en.wikipedia.org/wiki/Jet_(particle_physics)
Peccei-Quinn Theory - Wikipedia
https://en.wikipedia.org/wiki/Peccei%E2%80%93Quinn_theory
Axion - Wikipedia
https://en.wikipedia.org/wiki/Axion