Deadly Coincidence (sources)
- Flora, vol. 34, No. 44, November 28, 1851 Regensburg, Germany. Pg. 689, 702. Online [in German]: https://books.google.com/books?id=SkAXAAAAYAAJ&pg=PA702&lpg=PA702&dq=Filipstad+Risell&source=bl&ots=3dN3rADpJ0&sig=eFb9Lc2fIb6VgCoHg2FUDY6sx-U&hl=en&sa=X&ved=2ahUKEwjUxei9r7vcAhXECDQIHe06DjA4ChDoATAAegQIABAB#v=onepage&q=Filipstad%20Risell&f=false
- Carolus Linnaeus: Ein Lebensbild, by Dr. Johannes Fr. X. Gistel, 1878 J.D. Sauerlander's Verlag, Frankfurt, Germany. Pg. 198. Online at: https://books.google.com/books?id=jq6VPG2zmUkC&pg=PR24&dq=Carolus+Linnaeus:+Ein+Lebensbild&hl=en&sa=X&ei=Q0K3VKeIGIu6yQS904DoCA&ved=0CCwQ6AEwAQ#v=snippet&q=carl%20clerk&f=false
- Nemesis Divina, by Carl von Linne (Carolus Linnaeus), translated by M.J. Petry, 2001. Pg. 112. Online [preview]: https://books.google.com/books?id=Fw7wCAAAQBAJ&printsec=frontcover&dq=Carolus+linnaeus+%22Nemesis+Divina%22+history&hl=en&sa=X&ved=0ahUKEwjUx6iSuLvcAhUKE3wKHWrbDs8QuwUIKjAA#v=snippet&q=risell%20filipstad&f=false