Gartner: E-learning Market Pushing Toward Open Source
Interview on the increase of open source LMSs Moodle and Sakai in higher education
A Guide to K-12 Open Source LMS Options -- THE Journal
Overview of open source LMS options with examples of districts currently using them. This article covers Moodle, Sakai, Canvas, OLAT, ATutor, and Google CloudCourse. I thought CloudCourse was owned by Google, but it appears the code has an Apache license. CloudCourse seems to be mostly scheduling rather than a full-fledged LMS.
Open source software for elearning – matbury.com
List of open source applications for creating e-learning. Most of these aren't specifically designed for creating online learning, but can be used that way. The list is divided into desktop software like Audacity and CamStudio and server software like Moodle and MediaWiki.
Totara vs Moodle - Moodle For BusinesseseLearning Experts | Paradiso Solutions
Screenshots and overview of Totara's features that can make it a better fit for businesses than default Moodle.
The Top 8 Free/Open Source LMSs - Capterra Blog
This is actually 18+ free and/or open source LMSs. Some are truly open source, some are freemium or other business models. If you want a list that goes well beyond Moodle and Canvas, this is a good place to start.