Relativistic center-of-mass variables and the harmonic oscillator quark model calculation of the nucleon magnetic moment and the axial-vector coupling constant: A. Ilakovac and D. Tadić, Zavod za teorijsku fiziku, Prirodoslovno-matematički fakultet, University of Zagreb, Zagreb, Croatia, Yugoslavia; F. A. B. Coutinho, Instituto de Física, Universidade de Sao Paulo, Sao Paulo, Brazil; F. Krmpotić, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, La Plata, Argentina