How many publication citations does Marshall W. van Alstyne's co-author and author of Internetwork externalities and free information goods, have?
3143
Geoffrey G Parker was born in Sidcup, Kent in 1973. He was a distinguished visiting scholar at Christ's College, Cambridge. Eng. (Boston, MA). He was later appointed the George F. <unk>nParkes.
[INST]
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Question: How many publication citations does Marshall W. van Alstyne's co-author and author of Internetwork externalities and free information goods, have?
Context: Geoffrey G Parker was born in Sidcup, Kent in 1973. He was a distinguished visiting scholar at Christ's College, Cambridge. Eng. (Boston, MA). He was later appointed the George F. <unk>nParkes.
[/INST] Answer:
