1. Lin Y, Tian J: A survey on medical image segmentation methods. Pattern Recognit Artif Inteligence. 2002, 15 (2): 192-204.
2. http://en.wikipedia.org/wiki/Thyroid,
3. http://en.wikipedia.org/wiki/Fine-needle_aspiration,
4. http://en.wikipedia.org/wiki/Single-photon_emission_computed_tomography,
5. http://en.wikipedia.org/wiki/Medical_imaging,