Colored Quaternion Dirac Particles of Charges 2/3 and -1/3
  By starting with the simpliest expression of the first order linear wave equation (Dirac's equation) and by confining the elements of the coefficients (matrices) to the quaternions, it is shown that the association of the imaginary bases of the quaternions with three "colors" and their conserved currents results in quasi-particles with charges of 2/3 and -1/3 with a minimum of assumptions. It is shown how color neutral particles are required by Q covariance, first discussed by Finkelstein, et. al. in 1963. 
Lester C. Welch