APA

Graham D. Y., Tabibian N., Michaletz P. A., Kinner B. M., Schwartz J. T., Heiser M. C., Dixon W. B. & Smith J. L. (19890920). Endoscopic needle biopsy: a comparative study of forceps biopsy, two different types of needles, and salvage cytology in gastrointestinal cancer. : Gastrointestinal endoscopy.

Chicago

Graham D Y, Tabibian N, Michaletz P A, Kinner B M, Schwartz J T, Heiser M C, Dixon W B and Smith J L. 19890920. Endoscopic needle biopsy: a comparative study of forceps biopsy, two different types of needles, and salvage cytology in gastrointestinal cancer. : Gastrointestinal endoscopy.

Harvard

Graham D. Y., Tabibian N., Michaletz P. A., Kinner B. M., Schwartz J. T., Heiser M. C., Dixon W. B. and Smith J. L. (19890920). Endoscopic needle biopsy: a comparative study of forceps biopsy, two different types of needles, and salvage cytology in gastrointestinal cancer. : Gastrointestinal endoscopy.

MLA

Graham D Y, Tabibian N, Michaletz P A, Kinner B M, Schwartz J T, Heiser M C, Dixon W B and Smith J L. Endoscopic needle biopsy: a comparative study of forceps biopsy, two different types of needles, and salvage cytology in gastrointestinal cancer. : Gastrointestinal endoscopy. 19890920.