On the Color-Singlet States in Many-Quark Model with the su(4)-Algebraic   Structure. I --- Color-Symmetric Form ---
  In the modified Bonn quark model in which quark-pairing and particle-hole interactions are included, color-singlet states are examined in addition to the color-neutral quark-triplet state by a method of boson realization. The region which consists of single-quarks, quark pairs and quark triplets is analyzed. 
Y.Tsue (Kochi Univ., Japan), C. Providencia (Univ. de Coimbra,   Portugal), J. da Providencia (Univ. de Coimbra, Portugal), ...
nucl-th hep-ph