Latent fingerprints are the fingerprint which are invisible and the are made visible after applying some chemical over them. These are left unintentionally by the criminals at crime scene.
There is immense literature on latent fingerprint research all over the world. you may look into books on fingerprints and forensic anthropology. Latent fingerprints can be developed with F P POWDERS from hard and plane surfaces, chemical solutions of silver nitrate or ninhydrine can be used on rough surfaces,lasor beams can also be used for developing latent prints . comparison can be manual or with equipments like FACTS OR AFIS which are computerised and automated.