In Re Adoption of Zimmerman , 229 N.W.2d 245 ( 1975 )
In Re the Adoption of Keithley , 206 N.W.2d 707 ( 1973 )
In Re Adoption of Vogt , 219 N.W.2d 529 ( 1974 )
In Re the Adoption of Clark , 183 N.W.2d 179 ( 1971 )