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The so-called ‘Leiden Conventions’ are almost universally used in the fields of Greek and Latin epigraphy and in Greek and Latin papyrology. Please check out the Leiden Conventions Wikipedia article. Most of the encodings used there are correct, except for the interlinear addition markers, for which see below under Conversion to typeset text, \ / (backslash, forward slash).

Other frequently-used symbols

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[[]] (two opening square brackets, two closing square brackets) used to enclose text deleted in the ancient document but still legible or restorable. [⁠[ must be changed to ⟦ ‘left white square bracket’, U+27E6; ]⁠] must be changed to ⟧ ‘right white square bracket’, U+27E7.

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