(a) inscribed in pencil on reverse l.r.: A1 (b) inscribed in pencil on reverse l.r.: A2 (c) inscribed in pencil on reverse l.r.: B1 (d) inscribed in pencil on reverse l.r.: B2 (e) inscribed in pencil on reverse l.r.: C1 (f) inscribed in pencil on reverse l.r.: C2