Discovery of Gallium, Germanium, Lutetium, and Hafnium Isotopes
  Currently, twenty-eight gallium, thirty-one germanium, thirty-five lutetium, and thirty-six hafnium isotopes have been observed and the discovery of these isotopes is discussed here. For each isotope a brief synopsis of the first refereed publication, including the production and identification method, is presented. 
J.L. Gross and M. Thoennessen
nucl-ex