inscribed in fibre-tipped pen l.l.: 2/15 inscribed in fibre-tipped pen l.r.: Matthew Sleeth (underlined) inscribed in fibre-tipped pen on reverse l.l.: 2/15 inscribed in fibre-tipped pen on reverse l.c.: UNTITLED #21 from OPFIKON, 1997/2004 inscribed in fibre-tipped pen on reverse l.r.: Matthew Sleeth (underlined) / IMP.
