The upper lip is derived from
The upper lip is formed by the fusion of two maxillary prominences with the two medial nasal prominences Ref : Langman's Medical Embryology 14e pg 295,298.
Maxillary prominence and mandibular prominence
Maxillary prominence and medial nasal prominence
Maxillary prominence and lateral nasal prominence
Mandibular prominence and medial nasal prominence
General anatomy