The unfilled survey of the Corona Borealis region contains the velocities of 82 galaxies from 6 well separated conic sections of space.
data("galaxy")galaxy is a data frame with 82 cases (rows) and 1 continuous variable (columns) called Velocity.
S. Richardson and P. J. Green. On bayesian analysis of mixtures with an unknown number of components. Journal of the Royal Statistical Society B, 59(4):731-792, 1997. https://www.jstor.org/stable/2985194. G. McLachlan and D. Peel. Contribution to the discussion of paper by s. richardson and p.j. green. Journal of the Royal Statistical Society B, 59(4):779-780, 1997. https://www.jstor.org/stable/2985194. M. Stephens. Bayesian analysis of mixture models with an unknown number of components - an alternative to reversible jump methods. The Annals of Statistics, 28(1):40-74, 2000. https://www.jstor.org/stable/2673981.