Cordón, Luis A. (2005). Popular Psychology: An Encyclopedia. Westport, Conn: Greenwood Press. p. 182. ISBN978-0-313-32457-4. «The essential problem is that a large portion of the scientific community, including most research psychologists, regards parapsychology as a pseudoscience, due largely to its failure to move beyond null results in the way science usually does. Ordinarily, when experimental evidence fails repeatedly to support a hypothesis, that hypothesis is abandoned. Within parapsychology, however, more than a century of experimentation has failed even to conclusively demonstrate the mere existence of paranormal phenomenon, yet parapsychologists continue to pursue that elusive goal.»
Friedlander, Michael W. (1998). At the Fringes of Science. Boulder, Colorado: Westview Press. p. 119. ISBN978-0-8133-2200-1. «Parapsychology has failed to gain general scientific acceptance even for its improved methods and claimed successes, and it is still treated with a lopsided ambivalence among the scientific community. Most scientists write it off as pseudoscience unworthy of their time.»
