Looks like a yahoo.com spider was trying to or did index your site.
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68.142.251.154...
OrgName: Inktomi Corporation
OrgID: INKT
Address: 701 First Ave
City: Sunnyvale
StateProv: CA
PostalCode: 94089
Country: US
NetRange: 68.142.192.0 - 68.142.255.255
CIDR: 68.142.192.0/18
NetName: INKTOMI-BLK-4
NetHandle: NET-68-142-192-0-1
Parent: NET-68-0-0-0-0
NetType: Direct Allocation
NameServer: NS1.YAHOO.COM
NameServer: NS2.YAHOO.COM
NameServer: NS3.YAHOO.COM
NameServer: NS4.YAHOO.COM
NameServer: NS5.YAHOO.COM
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68.142.249.158...
OrgName: Inktomi Corporation
OrgID: INKT
Address: 701 First Ave
City: Sunnyvale
StateProv: CA
PostalCode: 94089
Country: US
NetRange: 68.142.192.0 - 68.142.255.255
CIDR: 68.142.192.0/18
NetName: INKTOMI-BLK-4
NetHandle: NET-68-142-192-0-1
Parent: NET-68-0-0-0-0
NetType: Direct Allocation
NameServer: NS1.YAHOO.COM
NameServer: NS2.YAHOO.COM
NameServer: NS3.YAHOO.COM
NameServer: NS4.YAHOO.COM
NameServer: NS5.YAHOO.COM
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More info on robots
Here ....