Historical clue formulations

• Cow, in Cádiz — 2020-10-25
• Cow, in Colombia — 2015-09-10
• Cow, in Cádiz — 2011-04-24
• Explorer Cabeza de ___ — 2009-12-30
• Cow: Sp. — 2008-08-21
• Cow: Sp. — 2006-12-23
• Explorer Cabeza de ___ — 2001-12-27
• Explorer Cabeza de ___ — 1997-11-22