D. F. Wilken

• Summary of Illinois farm business records, 1962, 38th annual
• Summary of Illinois farm business records, 1969, 45th annual
• Summary of Illinois farm business records, 1970, 46th annual
• Summary of Illinois farm business records, 1971, 47th annual
• Summary of Illinois farm business records, 1972, 48th annual
• Summary of Illinois farm business records, 1973, 49th annual
• Summary of Illinois farm business records, 1974, 50th annual
• Summary of Illinois farm business records, 1975, 51st annual
• Summary of Illinois farm business records, 1981, 57th annual
• Summary of Illinois farm business records, 1982, 58th annual
• Summary of Illinois farm business records, 1983, 59th annual
• Summary of Illinois Farm Business Records, 1962, 38th Annual; 874