As mentioned previously, a volume on the Shephelah in the Iron Age was just publilshed, edited by Oded Lipschits and myself. In the volume, there is a chapter on the excavations at Safi:
Maeir, A. M. 2017. Philistine Gath After 20 Years: Regional Perspectives on the Iron Age at Tell es-Safi/Gath. Pp. 133–54 in The Shephelah during the Iron Age: Recent Archaeological Studies, eds. O. Lipschits and A. M. Maeir. Winona Lake, IN: Eisenbrauns.
Here is a link to a PDF of the article: Maeir_Iron Age after 20 years at Safi_in Lipschits and Maeir eds. Iron Age Shephelah_Winona Lake 2017
This article is published in:
The Shephelah during the Iron Age: Recent Archaeological Studies, eds. O. Lipschits and A. M. Maeir. Winona Lake, IN: Eisenbrauns, 2017, copyright © 2017 by Eisenbrauns; placed here by permission of the publisher. The book may be purchased at: http://www.eisenbrauns.com/item/LIPSHEPHE