1. Akers PE. Partial dentures. J Am Dent Assoc. 1928;15:717–22.
2. Ancowitz S. Esthetic removable partial dentures. Gen Dent. 2004;52:453–9.
3. Aviv I, Ben-Ur Z, Cardash HS, Fatael H. RLS–the lingually retained clasp assembly for distal extension removable partial dentures. Quintessence Int. 1990;21:221–3.
4. Balvinder SS, Mittal D. An overview of removable partial denture. Indian J Dent Sci. 2012;3:117–24.
5. Belles DM. The twin flex clasp: an esthetic alternative. J Prosthet Dent. 1997;77:450–2.