[1] hOCR - OCR Workflow and Output embedded in HTML () <https://kba.github.io/hocr-spec/1.2/>
[2] hocr-spec/spec.md at master · kba/hocr-spec () <https://github.com/kba/hocr-spec/blob/master/1.1/spec.md>
[3] kba/hocr-spec: The hOCR Embedded OCR Workflow and Output Format () <https://github.com/kba/hocr-spec>
[4] hOCR - Wikipedia () <https://en.wikipedia.org/wiki/HOCR>