Search for GUT Magnetic Monopoles with the MACRO Experiment at the Gran   Sasso Lab
  The final results of the MACRO experiment on the search for GUT supermassive magnetic monopoles in the penetrating cosmic radiation are presented and discussed. The 90% CL upper limits are at the level of 1.5 - 2 x 10^-16 cm^-2 s^-1 sr^-1 for 0.0004 < beta < 1. Similar limits were obtained for nuclearites. Limits for the MM catalysis of proton decay are at 3 - 4 x 10^-16 cm^-2 s^-1 sr^-2 for 10^-4 < beta < 6 x 10^-3. 
G. Giacomelli (Bologna University and INFN) (for the MACRO Coll)