@misc{indiciaec942bbaec4a9,
  title = {Experimental constraints on a stringy SU(5) x U(1) model.},
  author = {JL Lopez and DV Nanopoulos and A Zichichi},
  year = {1996},
  doi = {10.1103/physrevd.53.5253},
  url = {https://pubmed.ncbi.nlm.nih.gov/10020521/},
  note = {Source identifier: 10020521}
}