https://www.bizjournals.com/denver/blog/boosters_bits/2016/02/amazon-sales-tax-collection-begins-in-colorado-but.html

https://sellercentral.amazon.com/gp/help/external/help.html

https://www.reddit.com/r/Colorado/comments/43x5nf/amazon_sales_tax_collection_begins_in_colorado/

https://www.avalara.com/taxrates/en/blog/2016/01/amazon-to-collect-colorado-sales-tax-february-2016.html

https://www.denverpost.com/2016/01/15/amazon-to-collect-colorado-sales-tax-on-purchases-starting-feb-1/

https://www.amazon.com/gp/help/customer/display.html/ref=hp_left_v4_sib

https://www.cml.org/home/advocacy-legal/Members39-Guide-to-Legal-Consulting-Services-and-Amicus-Briefs/cml-model-ordinance---economic-nexus-marketplace-facilitators

https://www.reddit.com/r/Denver/comments/40yew5/colorado_use_tax/

https://www.reddit.com/r/Denver/comments/6fmt09/colorado_has_one_of_the_most_complicated_sales/

https://sellercentral.amazon.com/forums/t/colorado-sales-tax/451573/11

https://sellercentral.amazon.com/forums/t/colorado-sales-tax/451573/5

https://www.denverpost.com/2017/07/07/colorados-amazon-tax-law-meaning/

https://tax.colorado.gov/consumer-use-tax

https://tax.colorado.gov/consumer-use-tax-filing-information

https://tax.colorado.gov/consumer-use-FAQ

https://www.denverpost.com/2014/02/19/denver-judge-temporarily-blocks-colorados-amazon-tax-law/

https://sellercentral.amazon.com/gp/help/external/LHTNXZHNADQ7Q66

https://www.npr.org/sections/money/2013/04/16/177384487/most-people-are-supposed-to-pay-this-tax

https://www.reddit.com/r/FulfillmentByAmazon/comments/8vab57/please_help_me_understand_state_sales_tax/

https://www.reddit.com/r/tax/comments/61w7s2/reporting_consumer_use_tax_to_co/

https://ttlc.intuit.com/community/taxes/discussion/do-i-need-to-include-online-purchases-on-my-tax-return-if-i-paid-sales-tax-on-all-of-them-at-the/00/631314

https://colorado.ttr.services/

https://kool1079.com/colorados-amazon-tax/