"The science of Psychology has been far more successful on the negative than on the positive side"
- Abraham Maslow
https://ppc.sas.upenn.edu/sites/ppc.sas.upenn.edu/files/ppintroarticle.pdf
https://www.youtube.com/watch?v=9FBxfd7DL3E
https://www.youtube.com/watch?v=4q1dgn_C0AU
http://www.bmj.com/content/337/bmj.a2338?view=long&pmid=19056788
http://www.dailymail.co.uk/news/article-1095783/People-exercise-work-days-happier-suffer-stress-productive.html
http://www.people.hbs.edu/mnorton/aknin%20norton%20dunn%202009.pdf
http://greatergood.berkeley.edu/images/application_uploads/norton-spendingmoney.pdf
http://www.eurekalert.org/pub_releases/2011-02/msu-sfa022211.php
https://ppc.sas.upenn.edu/sites/ppc.sas.upenn.edu/files/balancedpsychologyarticle.pdf
https://ppc.sas.upenn.edu/sites/ppc.sas.upenn.edu/files/positivehealth2008article.pdf
https://ppc.sas.upenn.edu/sites/ppc.sas.upenn.edu/files/positivepsychotherapyarticle.pdf
http://mina.education.ucsb.edu/janeconoley/ed197/documents/Froh_TheHistoryofPosPsych.pdf
https://www.ted.com/talks/ron_gutman_the_hidden_power_of_smiling/transcript?language=en
http://www.ted.com/talks/mihaly_csikszentmihalyi_on_flow
http://www.simplypsychology.org/perspective.html
http://www.pursuit-of-happiness.org/history-of-happiness/martin-seligman-positive-psychology/
https://en.wikipedia.org/wiki/Positive_psychology
https://en.wikipedia.org/wiki/Martin_Seligman
https://en.wikipedia.org/wiki/Mihaly_Csikszentmihalyi