Editorial Staff, . (2005). Britannica: Ready Reference Encyclopedia vol-8 {P to S}. new delhi: Enclyclopedia Britannica.
Editorial Staff, . 2005. Britannica: Ready Reference Encyclopedia vol-8 {P to S}. new delhi: Enclyclopedia Britannica.
Editorial Staff, . Britannica: Ready Reference Encyclopedia vol-8 {P to S}. new delhi: Enclyclopedia Britannica. 2005.
