@article{6659,
  author = {Douglas Gough and W. Merryfield and Juri Toomre},
  title = {Phase Inversion: Inferring Solar Subphotospheric Flow and Other Asphericity from the Distortion of Acoustic Waves},
  year = {1998},
  journal = {The Astrophysical Journal},
  volume = {501},
  pages = {882-894},
  month = {1098-07},
  issn = {0004-637X},
  doi = {10.1086/305843},
}