The primary source of the article "A brief history of globalization" by Peter Vanham is the author himself, as he is the one providing the information and analysis. However, there is a possibility that Peter Vanham used various secondary sources to gather information and shape his understanding of globalization. These secondary sources could include academic research, historical documents, and reference materials from other experts in the field of globalization and economic history. Without further information from the article or the author, it is difficult to determine specific secondary sources used.
