Image Rollovers for Mobile and Non-Mobile Email http://freshinbox.com/blog/image-rollovers-for-mobile-and-non-mobile-email/
Keep High-Density Displays from Uglifying Your Emails http://blog.mailchimp.com/keep-high-density-displays-from-uglifying-your-emails/
Removing spacing from around tables in Outlook 2007 and 2010 https://www.campaignmonitor.com/blog/post/3694/removing-spacing-from-around-tables-in-outlook-2007-and-2010/
Why can’t I get my HTML email to look great on Android devices? https://www.campaignmonitor.com/blog/post/3638/why-cant-i-get-my-html-email-to-look-great-on-android-devices/
Using @media to bypass max-width http://stylecampaign.com/blog/2011/08/using-media-to-bypass-max-width/
The Best Way to Code Background Colors for HTML Email https://litmus.com/blog/background-colors-html-email