John B. Sparks
2010, Timeline, Global
Adam Hart-Davis
2007, Timeline, Global
Pat Daniels; Steve Hyslop
2003, Timeline, Global
Neil Kagan
2006, Timeline, Global
National Geographic; Douglas Brinkley
2005, Timeline, Global
DK Publishing
2011, Timeline, Global
Richard J. Overy
2010, Timeline, Global
Bernard Grun; Eva Simpson
2005, Timeline, Global
Usefulcharts
2012, Timeline, Global
John B. Teeple
2006, Timeline, Global
Andreas Nothiger
2004, Timeline, Global