Eigenvalues of Large Sample Covariance Matrices of Spiked Population   Models
  We consider a spiked population model, proposed by Johnstone, whose population eigenvalues are all unit except for a few fixed eigenvalues. The question is to determine how the sample eigenvalues depend on the non-unit population ones when both sample size and population size become large. This paper completely determines the almost sure limits for a general class of samples. 
Jinho Baik and Jack W. Silverstein