Answer
References
Laux, R., & Culvert, L.L. (2020). Ultrasound. In J.L. Longe (Ed.), The Gale encyclopedia of medicine (6th ed., pp. 5307-5309). Gale.
Parenthetical citation: (Laux & Culvert, 2020)
Narrative citation: Laux & Culvert (2020) state that an ultrasound is considered a safe, non-invasive procedure.
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