Linked from
The 12 pages that link to Presbyopia, each with the reason it gives.
Crystalline lensRelated: A stiffer lens becomes less able to increase its curvature for near vision.
EyeglassesRelated: Reading glasses and multifocal lenses compensate for reduced near focusing.
BifocalsRelated: Bifocals commonly correct the near-focus difficulty caused by presbyopia.
Blurred visionRelated: Near blur that develops with age often reflects reduced accommodation.