@conference{low-cost-pc-plug-in,
  author = {W. M. Zabolotny and W. Zaworski and D. Czarkowski},
  title = "Low cost {PC} plug-in Card for Digital Processing
           of Transcranial Doppler Signal",
  booktitle = "Proceedings of the XX-th National Conference Circuit
               Theory and Electronic Networks",
  year = 1997,
  pages = "457--461"}