The 4 O'Clock Murders by Scott Anderson

We couldn't find a cover image for this book but we did find it listed on Amazon

Important places

Colorado City (9)
Dallas (314)
Houston (225)

Counties

Mohave (17)
Harris (242)
Dallas (338)

Regions

Colorado (1,596)
Arizona (1,022)
California (7,435)
Texas (2,882)

Countries

Mexico (1,563)
United States (64,950)

Other geographical areas

Grand Canyon (19)
Front Range (USA) (58)
Colorado Plateau (62)
Central Valley (290)
Sierra Nevada (316)
Rocky Mountains (370)
Southwestern United States (1,729)
Great Plains (2,255)
Gulf Coast (USA) (2,573)
Northern California (3,440)