Here is another National Cancer Institute study, about construction of DNA molecules.
Recombineering: a homologous recombination-based method of genetic engineering. Sharan et al., Nat, Protoc. 2009;4(2):206023.

http://www.ncbi.nlm.nih.gov/pubmed/19180090

(PubMed.gov is an online series of reports from the U.S. National Institute of Health).