Analysis of information sources in references of the Wikipedia article "Bopomofo" in English language version.
The term "Bopomofo" is derived from the first four characters of the system's alphabet [ㄅㄆㄇㄈ – B'P'M'F'].
韻符「ㄭ」，陰平調號「¯」，注音時省略不標{...}陰平 以一短橫代表高平之聲調，注音時可省略不標。標注在字音最後一個符號右上角。
the rhyme symbol, "ㄭ", and the mark of Yin-ping tone, "¯", could be left out on Bopomofo notes.{...}This high and level tone is noted as a short dash mark and could be left out in Bopomofo note. If it is noted, it should be put on the upper right corner of the last Bopomofo note.
