![Current Research on Multiple Births | Acta geneticae medicae et gemellologiae: twin research | Cambridge Core Current Research on Multiple Births | Acta geneticae medicae et gemellologiae: twin research | Cambridge Core](https://static.cambridge.org/content/id/urn%3Acambridge.org%3Aid%3Aarticle%3AS0001566000004815/resource/name/firstPage-S0001566000004815a.jpg)
Current Research on Multiple Births | Acta geneticae medicae et gemellologiae: twin research | Cambridge Core
semantic markup - w3c html validation error - Section lacks heading. Consider using h2-h6 elements to add identifying headings to all sections - Stack Overflow
validator warnings: Section lacks heading. Consider using “h2”-“h6” elements to add identifying headings to all sections. · Issue #1678 · w3c/aria-practices · GitHub
![aria role not allowed on aside (dialog) element (per w3c validator) · Issue #2226 · material-components/material-components-web · GitHub aria role not allowed on aside (dialog) element (per w3c validator) · Issue #2226 · material-components/material-components-web · GitHub](https://user-images.githubusercontent.com/12751611/36064814-94459664-0e56-11e8-815a-0287a1f610dc.png)
aria role not allowed on aside (dialog) element (per w3c validator) · Issue #2226 · material-components/material-components-web · GitHub
W3C: "Section lacks heading. Consider using h2-h6 elements to add identifying headings to all sections." · Issue #6 · markdown-it/markdown-it-footnote · GitHub
![تويتر \ Ross Guberman على تويتر: "The second puzzle piece links the second part of the first with doctrine. The third and fourth then weave together lines of equal protection cases over تويتر \ Ross Guberman على تويتر: "The second puzzle piece links the second part of the first with doctrine. The third and fourth then weave together lines of equal protection cases over](https://pbs.twimg.com/media/E6hS15eXoAI-4li.png)
تويتر \ Ross Guberman على تويتر: "The second puzzle piece links the second part of the first with doctrine. The third and fourth then weave together lines of equal protection cases over
W3C: "Section lacks heading. Consider using h2-h6 elements to add identifying headings to all sections." · Issue #6 · markdown-it/markdown-it-footnote · GitHub
![Headings, Lists & Tables for Accessibility | Center for Learning Experimentation, Application, and Research Headings, Lists & Tables for Accessibility | Center for Learning Experimentation, Application, and Research](https://clear.unt.edu/sites/default/files/uploads/a11y_-_jaws-header-list.png)