La formulazione con sfera a minimo raggio è stata introdotta dallo stesso Vapnik per problemi di classificazione multipla. Successivamente è stata adoperata per problemi di One-class classification e per problemi di regressione. Infine per il Support Vector Clustering.

Approfondire:

• bibtex | link
  B. Schölkopf, C. Burges, and V. Vapnik, "Extracting support data for a given task," in First International Conference on Knowledge Discovery & Data Mining, Menlo Park, 1995.
  @inproceedings{sch95extracting, Address = {Menlo Park},
  Author = {B. Sch”olkopf and C. Burges and V. Vapnik},
  Booktitle = {First International Conference on Knowledge Discovery & Data Mining},
  Date-Added = {2007-05-07 12:59:25 +0200},
  Date-Modified = {2007-06-19 11:32:17 +0200},
  Editor = {U. M. Fayyad and R. Uthurusamy},
  Keywords = {svm},
  Publisher = {AAAI Press},
  Title = {Extracting support data for a given task},
  Url = {http://citeseer.ist.psu.edu/sch95extracting.html},
  Year = {1995},
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  Bdsk-Url-1 = {http://citeseer.ist.psu.edu/sch95extracting.html}
}

• bibtex | link
  D. M. J. Tax and R. P. W. Duin, "Data Domain Description using Support Vectors," in European Symposium on Artificial Neural Network, Bruges (Belgium), 1999, pp. 251-256.
  @inproceedings{es1999, Address = {Bruges (Belgium)},
  Author = {David M. J. Tax and Robert P. W. Duin},
  Booktitle = {European Symposium on Artificial Neural Network},
  Date-Added = {2007-05-07 12:55:54 +0200},
  Date-Modified = {2007-06-23 08:24:18 +0200},
  Keywords = {SVM, domain description, SVDD, novelty detection, one-class},
  Month = {April},
  Pages = {251–256},
  Title = {Data Domain Description using Support Vectors},
  Url = {http://www.dice.ucl.ac.be/Proceedings/esann/esannpdf/es1999-458.pdf},
  Year = {1999},
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}

• bibtex | link
  J. Wang, P. Neskovic, and L. N. Cooper, "Pattern Classification Based on Minimum Bounding Spheres," in International Conference on Intelligent Computing, 2005, pp. 1969-1978.
  @inproceedings{icic05,
  author = {Jigang Wang and Predrag Neskovic and Leon N. Cooper},
  Booktitle = {International Conference on Intelligent Computing},
  Date-Added = {2007-05-07 13:10:15 +0200},
  Date-Modified = {2007-06-19 18:44:37 +0200},
  Keywords = {svm},
  Pages = {1969–1978},
  Title = {Pattern Classification Based on Minimum Bounding Spheres},
  Url = {http://www.physics.brown.edu/physics/userpages/faculty/Predrag_Neskovic/Publications/icic05-mbs.PDF},
  Year = {2005},
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}