Latent Dirichlet Allocation, David M. Blei, Andrew Y. Ng, Michael I. Jordan, 2003Journal of Machine Learning Research, Vol. 3 - The foundational paper introducing the Latent Dirichlet Allocation model.
Finding Scientific Topics, Thomas L. Griffiths, Mark Steyvers, 2004Proceedings of the National Academy of Sciences, Vol. 101 (National Academy of Sciences)DOI: 10.1073/pnas.0307752101 - Introduces and details the collapsed Gibbs sampling algorithm for Latent Dirichlet Allocation.
Bayesian Data Analysis, Andrew Gelman, John B. Carlin, Hal S. Stern, David B. Dunson, Aki Vehtari, Donald B. Rubin, 2013 (Chapman and Hall/CRC) - Comprehensive textbook on Bayesian statistical modeling and inference, including MCMC methods like Gibbs sampling.
Probabilistic Graphical Models: Principles and Techniques, Daphne Koller, Nir Friedman, 2009 (The MIT Press) - Authoritative textbook covering probabilistic graphical models, including details on LDA and various inference algorithms.