Hundreds of the discovered particles, called resonances, are produced in nucleon–nucleon, nucleon–nucleus and nucleus–nucleus collisions at high energies, when the nucleons and nuclei are accelerated (prior to collisions) to the velocities very close to the speed of light. Resonances have very short life times and decay almost instantaneously to the more stable particles, which are finally detected and measured by particle detectors. The commonly used technique for reconstruction of the mass distributions of resonances is called the method of Invariant Masses. The method of Invariant Masses, coupled with an angular criterion, for reconstruction of the mass distributions of delta0(1232) resonances and obtaining their momentum, transverse momentum, kinetic energy, emission angle and rapidity distributions was presented in detail. The history and present status of synchrophasotron and accelerator complex of JINR (Joint Institute for Nuclear Research, Dubna, Russia) were also outlined and illustrated by photos. The book can be interesting and useful for the students and young researchers in field of Nuclear and High Energy Physics and other Physics disciplines, for general knowledge.