perpetualperpetual calenderperpetual inventoryperpetual inventory methodperpetual motionperpetuitypersistentpersonal probabilitypersonal staffpersonnelpersonnel chartpersonnel information systempersonnel managerpersonnel reviewpersonnel training problemperspectiveperspective imageperspective mappingperspective projectionperthousandperturbationperturbation functionperturbation methodperturbation of cost vectorperturbation of linear operatorsperturbation of right hand side vectorperturbation theoryperturbed proportionpessimisticpessimistic estimatepessimistic timepesudo inversepetitio principiipetition de principepetty cashpffafianpffafian differential equationphasephase anglephase differencephase i problemphase ii problemphase of a complex numberphase of cosinusoidal oscillationphase of simple harmonic motionphase planephase platephase portraitphase spacephase velocity