About rational solution

Consider the following equation under the given conditions.

n^5f^2 - 5m -20vm^3 +16v^2m^5 = 0 (1)
Conditions: 0 < m, n < 1; v, f > 1

Assertion: (1) cannot be satisfied if all of m, n, v, f are rational.

Any comment about the correctness of the assertion and some relevant
reference will be appreciated.
.