▁sold ▁to ▁the ▁public ▁to ▁supply ▁the ▁demand ▁for ▁older ▁instruments . ▁These ▁instruments ▁can ▁be ▁distinguished ▁from ▁the ▁original s , ▁however , ▁by ▁dis cre pan cies ▁in ▁the ▁labels ▁of ▁the ▁viol in , ▁and ▁more ▁important ly , ▁the ▁work mans hip ▁and ▁type ▁of ▁the ▁instrument . ▁ ▁Because ▁no ▁viol in ▁has ▁ever ▁been ▁actually ▁discovered ▁to ▁have ▁been ▁made ▁by ▁T ie ffen bru cker , ▁the ▁current ▁belief ▁is ▁that ▁" D u iff op ru gg ar " ▁never ▁actually ▁made ▁any ▁viol ins , ▁but ▁rather ▁that ▁he ▁made ▁almost ▁only ▁l utes ▁and ▁sold ▁different ▁instruments ▁of ▁other ▁mak ers , ▁and ▁his ▁name ▁was ▁used ▁to ▁sell ▁a ▁brand ▁of ▁commercial ▁instruments ▁made ▁for ▁V u illaume . ▁ ▁References ▁ ▁Bibli ography ▁ ▁F arga , ▁Franz , ▁Vi ol ins ▁& ▁Vi olin ists . ▁Trans . ▁Eg on ▁Lar son ▁with ▁Bruno ▁Ra ik in . ▁New ▁York : ▁Frederick ▁A . ▁Pra ger , ▁ 1 9 6 9 . ▁ ▁" The ▁T ie ffen bru cker ▁family ▁and ▁its ▁collabor ators ", ▁ch . ▁XVI ▁in ▁Vi ol ▁and ▁L ute ▁Mak ers ▁of ▁Ven ice ▁ 1 4 9 0 – 1 6 3 0 ▁by ▁Stef ano ▁P io ▁( 2 0 1 2 ), ▁Ed . ▁Ven ice ▁Research , ▁. ▁Abstract ▁and ▁index ▁ ▁External ▁links ▁Encyclopedia ▁Smith son ian , ▁G asp ard ▁Du iff op ru gg ar ▁