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![Christopher Ryan](https://harper.yugasa.org/wp-content/themes/harpercollins/images/author_background_img.jpg)
Christopher Ryan
Christopher Ryan, Ph.D. is a research psychologist. Cacilda Jethá, M.D. is a practicing psychiatrist. They live in Barcelona, Spain.
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Christopher Ryan, Ph.D. is a research psychologist. Cacilda Jethá, M.D. is a practicing psychiatrist. They live in Barcelona, Spain.