"19. In thepresent case, the relevant assessmentyear-s 1999-2000. The maincontention of the Revenueis that the respondent cannot beallowed to claim deductionregarding lease equalzationchargessince as such there is no expresis provision regarding such deductionin the IT Act. However, it is apt to note here thatthe respondentcan be charged on y on real income whichcan be calculated only after apptyirg the prescribed method.The ITAct issilent onsuch deduction. For suchcalculation,it isobvious thatttLe respondent hasto take course of Guidance Note prescribedt'y tht ICAI if it is available.Only after applying suchmethcd which is prescribed in theGuidance Note, the respondent can show faii and realincomewhich is liable to tax under the lT Act. Therefore, itis wrong to say that the respondent claim€d deduction by virtue ofGuidanceNoterather it onlyapplie d the method of bifurcationas prescribed by the expert team lf ICAI. Further, a conjointreading of Section145of the IT A':t read with Section21 1 (unamendedlof theCompaniesArt makes it clear that therespondent is entitledto do su(h bifurcation and in ourview there is no illegalityinsuch bifurcation as it isaccordingto the principlesof larv Moreover, the rule ofinterpretationsays that when internal aid is not availablethenfor the proper interpretation of tlte statue, the Courtmay take the help of externalaid lf a terin is not defined in a statue,thenits meaning can be taken as is prevalent in ordinary or commercialparlance. Hence,n'e rlo not hnd any force in thecontentions of the Revenue thatthe accounting standardsprescribed bythe GuidanceNole