HubSpot Free Email Marketing - Powerful drag and drop email marketing in the HubSpot CRM
SaaS Marketer - Biweekly, insanely actionable SaaS marketing case studies.
Email Marketing: A Beginner's Guide - Master email marketing with these 3 short ebooks from Drip.
EnterpriseReady - A guide to building the SaaS features that enterprises love.
Email Marketing Academy from MailerLite - Learning platform for email marketing expert certification
Zero to Marketing - Short case studies that help you get better at marketing