@misc{indiciae1894d684968f,
  title = {Designs for group sequential tests.},
  author = {T R Fleming and D P Harrington and P C O'Brien},
  year = {1984},
  doi = {10.1016/s0197-2456(84)80014-8},
  url = {https://pubmed.ncbi.nlm.nih.gov/6518769/},
  note = {Source identifier: 6518769}
}