Help with ordering clothes from Boden?

okay, so i'm buying these - a href="http://www.boden.co.uk/en-GB/Teen-Girls-Shoes-Boots/99007-TAN/Teen-Girls-Tan-Suede-Moccasins.html" rel="nofollow"http://www.boden.co.uk/en-GB/Teen-Girls-…/a - from johnnie b, and i have a £10 off discount voucher, and 10% off code in the catalogue, and i was wondering if i could use them both, or can i only use one of them? thank you.