Using the legend provided, classify each of the following citations as to the location. A citation may have more than one answer. Legend: IRC = Internal Revenue Code FR = Federal Register IRB = Internal Revenue Bulletin NA = Not applicable CB = Cumulative Bulletin a. 61(a)(13). b. Prop.Reg. 1.3682(b)(1). c. Rev.Proc. 7737, 19772 C.B. 568. d. Temp.Reg. 1.1639T(b)(2)(I)(A). e. Rev.Rul. 6456, 19641 C.B. 133. f. Jack E. Golsen , 54 T.C. 742 (1970). g. Ltr.Rul. 9802018.