5 Ways to Accept Recurring Payments in 2017https://fitsmallbusiness.com/how-to-accept-recurring-payments/
AvaTax | Avalara Developerhttps://developer.avalara.com/avatax/
Dunning (process) - Wikipediahttps://en.wikipedia.org/wiki/Dunning_(process)
SaaS Subscriptions now available from AWS Marketplacehttps://aws.amazon.com/about-aws/whats-new/2016/11/saas-subscriptions-now-available-from-aws-marketplace/
Sales Tax Pitfalls for Subscription Based Businesses - Avalarahttps://www.avalara.com/us/en/learn/whitepapers/avoiding-sales-tax-pitfalls-recurring-revenue-business-model.html
Stripe Alternative | Cardinityhttps://cardinity.com/stripe-alternative
Stripe Billing | Hacker Newshttps://news.ycombinator.com/item?id=16766846