I've put my sources in this document as hyperlinks mark my message as spam:

[Rainfall] 
https://www.researchgate.net/figure/Precipitation-map-of-Iran_fig2_327115115

[Koppen Classification] 
https://www.researchgate.net/publication/359229969_Climate_of_Iran_according_to_Koppen-Geiger_Feddema_and_UNEP_climate_classifications

[This Source] 
https://ipad.fas.usda.gov/rssiws/al/metu_cropprod.aspx

[19th Century Journal, Page 617] 
https://archive.org/details/narrativeofjourn00frasuoft/page/616/mode/2up

[1] 
https://iranicaonline.org/articles/alborz-geography

[2] 
https://www.iranicaonline.org/articles/firuzkuh

[3] 
https://www.iranicaonline.org/articles/anti-alborz-the-highland-between-tehran-and-semnan-

[4] 
https://iranicaonline.org/articles/lavasan

[Tat people] 
https://en.wikipedia.org/wiki/Tat_people_(Iran)

[modern Iranian speakers] 
https://en.wikipedia.org/wiki/Tat_people_(Caucasus)