as m before certain consonants is no longer used: Shinbashi for . The version of the system published in the third (1954) and later editions of Kenkyusha's New Japanese-English Dictionary are often considered authoritative; it was adopted in 1989 by the Library of Congress as one of its ALA-LC romanizations, and is the most common variant of Hepburn romanization used today. In Japan itself, there are some variants officially mandated for various uses: , which mostly follows Modified Hepburn, except syllabic n is rendered as in Traditional. Japan Railways and other major railways use it for station names. , used for road signs, which otherwise follows Modified Hepburn closely but specifies that macrons are not to be used. , a permissive standard that renders the syllabic n as m before b, m and p. Most of the long vowels are not rendered. Moreover, this standard explicitly allows the use of in personal names, notably for passports. In particular, the long vowel ō can be romanized oh, oo or ou (Satoh, Satoo or Satou for ). Details of the variants can be found below. Obsolete variants The romanizations set out in the first and second versions of Hepburn's dictionary are primarily of historical interest. Notable differences from the third and later versions include: Second version and were written as ye: Yedo and were written as dzu: kudzu, tsudzuku , , and were written as kiya, kiyo and kiu (modern: ) was written as kuwa First version The following differences are in addition to those in the second version: was written as sz. was written as tsz. and were written as du. Features The main feature of Hepburn is that its orthography is based on English phonology. More technically, when syllables that are constructed systematically according to the Japanese syllabary contain an "unstable" consonant in the modern spoken language, the orthography is changed to something that better matches the real sound as an English-speaker would pronounce it. For example, is written shi not si. This transcription is thus only partly phonological. Some linguists such as Harold E. Palmer, Daniel Jones and Otto Jespersen object to Hepburn since the pronunciation-based spellings can obscure the systematic origins of Japanese phonetic structures, inflections, and conjugations. Since the vowel sounds in Hepburn are similar to the vowel sounds in Italian, and the consonants similar to those of many other languages, in particular English, speakers unfamiliar with