To express a recessive phenotype, the genotype must be homozygous (both genes must be recessive) for that recessive trait.
As for examples, I searched Google under the key words "recessive genes" to get these possible sources:
In the future, you can find the information you desire more quickly, if you use appropriate key words to do your own search. Also see http://hanlib.sou.edu/searchtools/.
I hope this helps. Thanks for asking.