I found 38k citations for The Nature of Statistical Learning Theory: https://scholar.google.com/scholar?cluster=86085598803682809...
And 25k for Statistical Learning Theory: https://scholar.google.com/scholar?cluster=86748554971781655...
My initial estimation of 10k was from a CiteSeer list that I didn't realize was limited to only documents in the CiteSeer database: http://citeseer.ist.psu.edu/stats/articles