@misc{indiciae6638b1d2972c,
  title = {Solution to the strong CP problem without an axion.},
  author = {KS Babu and RN Mohapatra},
  year = {1990},
  doi = {10.1103/physrevd.41.1286},
  url = {https://pubmed.ncbi.nlm.nih.gov/10012465/},
  note = {Source identifier: 10012465}
}