1. On unitary representations of the inhomogeneous Lorentz group;Wigner;Ann. Math.,1939
2. Group theoretical discussion of relativistic wave equations;Bargmann;Proc. Natl. Acad. Sci. USA,1948
3. Relativistic wave equations;Dirac;Proc. R. Soc. A,1936
4. Über den drehimpuls von teilichen mit ruhemasse null und beliebigem spin;Fierz;Helv. Phys. Acta,1939
5. On relativistic wave equations for particles of arbitrary spin in an electromagnetic field;Fierz;Proc. R. Soc. Lond. Ser. A, Math. Phys. Sci.,1939