The cuneiform sign for the syllable ab also represents that for ap, or the vowel and consonant usages of a, b, or p: in the Akkadian language "b" is unaspirated, formed with the lips, and "p" is aspir
Mesopotamian tablet for Sin-Kashid. Line 3, second character, ab. (Note that the second pair of horizontals angle up, and down, to the large vertical stroke anchoring the right of the "ab" sign.)
Ayyab's letter to Pharaoh, Amarna letter EA 364. His name is spelled in (line 2)--"um-ma A-iYa-aB, "...message (speaking), Ayyab..." (Note, for ab, the second pair of horizontals are at different angles.)
The cuneiform ma sign, is found in both the 14th century BC Amarna letters and the Epic of Gilgamesh. In the Epic it is also used as the Sumerogram MA,. The ma sign is often used at the end of words,
Amarna letter EA 365, "Furnishing Corvée Workers", Biridiya to Pharaoh, reverse (lines 15–30, (31)). 5th line from bottom, (line 23), "LÚ-MEŠ–ma-as-sà-meš (and)". Line 25, 3rd from bottom, repeats the long name. (high resolution, expandible photo)
Amarna letter EA 365 (reverse, top half), "Furnishing Corvée Workers", Biridiya to Pharaoh, (subject corvee labor, and townsites: Shunama, Yapu, and Nuribta). The "alphabetic" ma sign is used in the 7th line (Line 21), for URU-(city)-Šu-na-ma-ki, sixth character from left. [English: line 21: "in (i-na) 'City'-Shunama-(yours)"(ki)] (text reads left-to-right, with a common signature of the right side of some characters ending in vertical single, or multiple strokes). (high resolution, expandible photo)