| Http://: http://en.wikipedia.org/wiki/Von_Willebrand_disease |
| Http://: http://ghr.nlm.nih.gov/condition/von-willebrand-disease |
| Http://: http://en.wikipedia.org/wiki/Von_Willebrand_disease |
| Http://: http://ghr.nlm.nih.gov/condition/von-willebrand-disease |