Primary γ-Ray

primary beta ray

primary cosmic ray

primary cosmic-ray composition

primary medullary ray

primary X-ray

primary X-ray beam

gamma ray (=γ-ray)

net primary production per gross primary production ratio

primary element and primary weight analysis

primary parametric resonance and primary resonance

Primary resonance and primary parametric resonance

e-ray(extraordinary ray)

o-ray(ordinary ray)

21-Primary

21-Primary aminocorticoids

3 primary colors theory

3D simulation of primary and secondary equipment

3-primary-reformer method