Nizoral:
Ketoconazole shampoo: effect of long-term use in androgenic alopecia.
Ketoconazole as an adjunct to finasteride in the treatment of androgenetic alopecia in men.

Retin A:
Retinoids: compounds important to hair growth.
Topical tretinoin for hair growth promotion.

Proscar:
Hair growth effects of oral administration of finasteride, a steroid 5 alpha-reductase inhibitor, alone and in combination with topical minoxidil in the balding stumptail macaque.
Finasteride: the first 5 alpha-reductase inhibitor.
The effect of finasteride, a 5 alpha-reductase inhibitor, on scalp skin testosterone and dihydrotestosterone concentrations in patients with male pattern baldness.
The effects of finasteride (Proscar) on hair growth, hair cycle stage, and serum testosterone and dihydrotestosterone in adult male and female stumptail macaques (Macaca arctoides).
Comparison of finasteride (Proscar), a 5 alpha reductase inhibitor, and various commercial plant extracts in in vitro and in vivo 5 alpha reductase inhibition

Various:
Comparative efficacy of various treatment regimens for androgenetic alopecia in men.