Clear introductory sources on Egyptian group-writing

Question

I have come across the term group-writing (originally in a comment on this question but also elsewhere), apparently referring to a system the Egyptians used for transliterating foreign names. However, searching online has been surprisingly unhelpful in terms of finding reference material to understand what group-writing actually is; I guess because of a combination of obscurity and changing terminology.

I am looking for sources, preferably available freely online (I have JSTOR access but it is somewhat limited, and I'm not a member of an academic libraries), to understand what group-writing is. I'm a beginner when it comes to Egyptian but I'm comfortable reading technical material and just letting the extraneous detail wash over me.

Answer 1

The best introduction I've found is Hoch's Semitic Words in Egyptian Texts of the New Kingdom and Third Intermediate Period, specifically chapter 6, The Development of Group Writing. This chapter mainly covers Middle Kingdom group writing, where Egyptian ꜣ was used for Semitic r or l, but also describes how it developed into the much less systematic New Kingdom group writing where ꜣ was used for a (which is elaborated on elsewhere in the book).

For a short summary: in the Old and Middle Kingdom, "group writing" developed to transcribe foreign words and names. This mostly consisted of uniliteral signs for consonants followed by ỉ or y (for an i vowel) or w (for an u vowel); a vowels were generally left unmarked. In the New Kingdom, this developed into a much larger and less formalized system where groups of two or more signs represented syllables, including all vowels, using ꜣ for a.

Answer 2

I was recently pointed to Kilani's 2019 Vocalisation in Group Writing: A New Proposal, which is significantly more modern than Hoch and focuses on the principles underlying group-writing rather than the representations of individual Semitic words. It's also, conveniently, available to read for free.

Unlike Hoch, Kilani proposes that three types of "groups" were distinguished: "consonant next to a back vowel", "consonant not next to a back vowel", and "continuant that's part of a complex onset". This only allows two types of vowels to be distinguished (back and non-back), giving transcriptions like sArpUt for /sərp'ot/ "lotus". They also disagree on the interpretation of the sign Z4 (the dual strokes); Hoch claims this sign represents an /i/ vowel, while Kilani claims it's more like a diacritic, modifying the function of a neighboring group (for example, turning rA into r∅, or dA/d∅ into dU).