1. AJCC Cancer Staging Handbook,1998
2. Guidelines for radiotherapeutic techniques for cervical metastases from an unknown primary;Carlson;Int J Radiat Oncol Biol Phys,1986
3. Squamous cell carcinomas metastatic to cervical lymph nodes from an unknown head and neck mucosal site treated with radiation therapy alone or in combination with neck dissection;Erkal;Int J Radiat Oncol Biol Phys,2001
4. Palliation of visceral recurrences and metastases;Kagan,1997
5. Non-parametric estimation from incomplete observations;Kaplan;J Am Stat Assoc,1958