If you meant academic research regarding biological dogs, several recent and significant papers provide insight into their health and behavior:
A 2025 study in Animals (MDPI) and PMC found that dogs sleep more efficiently and spend more time in deep sleep (non-REM) when their owners are present. sleeping-dogs-links-pc
The paper Developmental features of sleep electrophysiology in family dogs discusses how sleep patterns change as dogs age, noting that a dog's central nervous system is often not fully mature even at 12 months. If you meant academic research regarding biological dogs,
For core controls and combat mechanics (like grappling with 'F' and striking with Left Click), Feral Interactive hosts the Official Game Manual . Sleeping Dogs™: Definitive Edition - manual - Feral
Sleeping Dogs™: Definitive Edition - manual - Feral Interactive
Research on ResearchGate explores the "interrelated effect of sleep and learning," showing that sleep may contribute significantly to memory consolidation in canines.