Veal heart ribonuclease P has an essential RNA component.

@article{Akaboshi1980VealHR,
  title={Veal heart ribonuclease P has an essential RNA component.},
  author={Eiko Akaboshi and Cecilia Guerrier-Takada and S. Altman},
  journal={Biochemical and biophysical research communications},
  year={1980},
  volume={96 2},
  pages={831-7}
}