Trust / Sources
Source Library
Authoritative sources cited in SEO Blitz content. We cite primary sources, peer-reviewed research, and recognized experts rather than secondary commentary.
Search Engines
Google Search Central
Google's official documentation for webmasters and content creators. This is the primary source for understanding how Google Search works and what Google recommends for content quality.
- Creating helpful, reliable, people-first content
- SEO Starter Guide
- How Google Search Results Work
- Google Search Central Blog
Google Search Quality Rater Guidelines
The internal guidelines used by Google's human quality raters. This document reveals what Google considers high-quality content and is essential for understanding E-E-A-T (Experience, Expertise, Authoritativeness, Trustworthiness).
Bing Webmaster Guidelines
Microsoft's official guidance for creating content that performs well in Bing search results.
Accessibility & Web Standards
W3C Web Content Accessibility Guidelines (WCAG)
The international standard for web accessibility. WCAG 2.1 Level AA is the target for most organizations and is referenced in legal requirements worldwide.
WebAIM
Web Accessibility In Mind, a nonprofit organization that provides practical accessibility guidance and tools.
MDN Web Docs
Mozilla's comprehensive documentation for web standards, HTML, CSS, and accessibility.
UX Research
Nielsen Norman Group
The leading voice in evidence-based UX research. NN/g has conducted thousands of user studies and publishes actionable findings for web designers and content creators.
Baymard Institute
Independent UX research organization with extensive studies on e-commerce usability and content presentation.
Plain Language
Plain Language Guidelines (U.S. Government)
Official guidelines for writing clearly and effectively. These principles apply to any content meant for general audiences.
Plain Language Association International (PLAIN)
Global organization promoting clear communication across contexts.
Readability Research
Flesch Reading Ease and Flesch-Kincaid Grade Level
The original readability formulas, developed by Rudolf Flesch in the 1940s and later adapted by the U.S. Navy. These formulas remain the standard for measuring text difficulty.
- Flesch, R. (1948). "A New Readability Yardstick". Journal of Applied Psychology, 32(3), 221-233.
- Kincaid, J. P., Fishburne, R. P., Rogers, R. L., & Chissom, B. S. (1975). "Derivation of New Readability Formulas". Naval Technical Training Command.
Gunning Fog Index
Readability formula developed by Robert Gunning that estimates the years of formal education needed to understand a text.
- Gunning, R. (1952). The Technique of Clear Writing. McGraw-Hill.
SMOG Index
Simple Measure of Gobbledygook, a readability formula for health communication that correlates strongly with reading comprehension.
- McLaughlin, G. H. (1969). "SMOG Grading: A New Readability Formula". Journal of Reading, 12(8), 639-646.
Coh-Metrix
Advanced text analysis tool that measures cohesion, syntactic complexity, and other dimensions of text difficulty.
- Graesser, A. C., McNamara, D. S., Louwerse, M. M., & Cai, Z. (2004). "Coh-Metrix: Analysis of Text on Cohesion and Language". Behavior Research Methods, Instruments, & Computers, 36(2), 193-202.
Content Strategy
Content Marketing Institute
Leading organization for content marketing education and research.
Copyblogger
Long-running resource for content creation and copywriting guidance.
How We Cite Sources
SEO Blitz content follows these citation practices:
- Primary sources first: We link to original research, official documentation, and direct statements rather than secondary commentary.
- Dates matter: We note publication dates for time-sensitive guidance and update when sources change.
- Context, not just links: We explain what a source says and why it matters, not just that it exists.
- No anonymous "studies show": Every claim attributed to research names the study, author, or institution.