| 5. | (UK) Nottingham University | | | Number Theory and Arithmetic Geometry research group. Research interests, members, visitors, meetings. www.maths.nott.ac.uk |
| 16. | (USA) Boston University | | | Algebra and Number Theory Research Group. Members, research interests, seminars, courses. math.bu.edu |
| 20. | (USA) Penn State | | | Algebra and number theory group. Members, seminars, preprints, links. www.math.psu.edu |
| 22. | (Austria) University of Vienna | | | Johannes Schoißengeier's number theory research group. Members, research interests, links to other Austrian number theorists. radon.mat.univie.ac.at |
| 24. | (USA) CUNY | | | Arithmetic Geometry Seminar meetings. math.gc.cuny.edu |
| 42. | (USA) Caltech | | | Underground Number Theory Seminar. Schedule of meetings. www.its.caltech.edu |
| 43. | (UK) Cardiff University | | | Number Theory Group. Members, research interests, advice to research students. www.cf.ac.uk |
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