2 9 0 ▁and ▁is ▁thought ▁to ▁be ▁contemporary ▁with ▁the ▁Ass isi ▁fres co es . ▁Ear lier ▁attributed ▁works ▁are ▁the ▁San ▁Giorg io ▁alla ▁Costa ▁Madonna ▁and ▁Child , ▁now ▁in ▁the ▁Dioc es an ▁Museum ▁of ▁Santo ▁Stef ano ▁al ▁P onte , ▁Florence , ▁and ▁the ▁signed ▁panel ▁of ▁the ▁St ig mat ization ▁of ▁St . ▁Francis ▁hous ed ▁in ▁the ▁Lou vre . ▁ ▁An ▁early ▁bi ographical ▁source , ▁Ric c ob al do ▁of ▁Ferr ara , ▁mentions ▁that ▁Gi otto ▁painted ▁at ▁Ass isi ▁but ▁does ▁not ▁specify ▁the ▁St ▁Francis ▁Cy cle : ▁" What ▁kind ▁of ▁art ▁[ Gi otto ] ▁made ▁is ▁test ified ▁to ▁by ▁works ▁done ▁by ▁him ▁in ▁the ▁Francis can ▁churches ▁at ▁Ass isi , ▁R im ini , ▁Pad ua ..." ▁Since ▁the ▁idea ▁was ▁put ▁forward ▁by ▁the ▁German ▁art ▁historian ▁Friedrich ▁R int elen ▁in ▁ 1 9 1 2 , ▁many ▁sch ol ars ▁have ▁expressed ▁doubt ▁that ▁Gi otto ▁was ▁the ▁author ▁of ▁the ▁Upper ▁Church ▁fres co es . ▁Without ▁documentation , ▁arguments ▁on ▁the ▁att ribution ▁have ▁re lied ▁upon ▁con no isseur ship , ▁a ▁not or iously ▁un re li able ▁" s cience ", ▁but ▁technical ▁exam in ations ▁and ▁compar isons ▁of ▁the ▁work shop ▁painting ▁processes ▁at ▁Ass isi ▁and ▁Pad ua ▁in ▁ 2 0 0 2 ▁have ▁provided ▁strong ▁evidence ▁that ▁Gi otto ▁did ▁not ▁paint ▁the ▁St . ▁Francis ▁Cy cle