I would assume the information was obtained by R. Ross Houston, whoever he is. It's certainly not found in the CSRs
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Regimental Casualty Analysis

04/02/65 Petersburg, VA, Killed 1*, Wounded 0, POW 0, Missing 0

* Alphonso Meadows
Residence Lowndes County AL;
Enlisted as a Private
"H" Co. AL 3rd Infantry

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Regiment Personnel Listing

Alphonso Meadows, Co. H, Enlisted, Out Date 04/02/65, Killed, Petersburg, VA

Sources used by Historical Data Systems, Inc.:
- Index to Compiled Confederate Military Service Records
- Research by R. Ross Houston