Source: www.tipitaka.net/pali/paliload.php?page=velthuis
The Velthuis Scheme
Double the vowels, Punctuate the consonants
This scheme was originally developed in 1991 by Frans Velthuis for use with hisdevnag Devanagari font, designed for the TeX typesetting system. Pali and Sanskrit scholars have since adopted it as a standard technique in Internet correspondence.
In the Velthuis scheme, two basic rules are observed:
1. Long vowels (those with a macron (bar) above them) are doubled: aa, ii, uu.
2. For consonants, the diacritic mark precedes the letter it affects. Thus, the retroflex (cerebral) consonants (those with a dot underneath) are: .r .t .th .d .dh .n .m .s .l. The guttural nasals (m or n with a dot above) are represented by "m and "n. The palatal nasal (n with a tilde) is ~n.
The scheme is precise, although it takes a while to get used to. Below is the affected Pali letters in both the original typeset form and Velthuis scheme.
(HL: The following table needs special font to read)
Typeset Velthuis Long vowels ā aa ī ii ū uu Consonants ń "n ñ ~n t ̣ .t t ̣h .th ḍ .d ḍh .dh ṇ .n l ̣ .l ṃ .m
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