Stability and variability of dream content.

@article{Schredl1998StabilityAV,
  title={Stability and variability of dream content.},
  author={Michael Schredl},
  journal={Perceptual and motor skills},
  year={1998},
  volume={86 2},
  pages={733-4}
}
The present study investigated the stability and variability, respectively, of selected dream content measures derived from diary dreams. The within-subject correlations were small when dream length was controlled. To obtain sufficient reliability for all scales dream series of 20 dreams or more would be necessary.