PT - JOURNAL ARTICLE AU - M Simpson AU - C Duncan AU - R Knight AU - M W J Strachan TI - An evolving headache AID - 10.1136/jnnp.2007.140970 DP - 2008 Jan 01 TA - Practical Neurology PG - 62--65 VI - 8 IP - 1 4099 - http://pn.bmj.com/content/8/1/62.short 4100 - http://pn.bmj.com/content/8/1/62.full SO - Pract Neurol2008 Jan 01; 8