@article{b. piura2006site,
  title={Placental site trophoblastic tumor - a challenging rare entity},
  author={b. piura},
  journal={European Journal of Gynaecological Oncology},
  volume={27},
  number={6},
  pages={545--551},
  doi = {10.12892/ejgo200606545},
  year={2006}
}