ブル・リング
↑ Copper Development Association UK: Copper in Architecture Design Award - Spiral Cafe, St Martin's Square, Birmingham Archived 2008年6月12日, at the Wayback Machine.
↑ Spatial Information Architecture Laboratory: Projects: Parametric Bridge Archived 2008年6月17日, at the Wayback Machine.
↑ BBC Birmingham: Art of the Bullring
↑ Sculptor finally given plaque tribute - icBirmingham, September 14, 2004 (Accessed March 17, 2007)
↑ Bully's put out of sight - Birmingham Mail, June 29, 2005 (Accessed March 17, 2007)
↑ Bull's creator backs name campaign, icbirmingham.co.uk, 2003年11月6日, accessed 2006年11月11日
↑ Brum's bull in new vandal attack - Birmingham Mail, February 6, 2006 (Accessed March 17, 2007)