diff --git a/doc/units.html b/doc/units.html
index d0cff8eac7..5e2f07de4c 100644
--- a/doc/units.html
+++ b/doc/units.html
@@ -45,7 +45,7 @@ results from a unitless LJ simulation into physical quantities.
 </P>
 <UL><LI>mass = mass or m
 <LI>distance = sigma, where x* = x / sigma
-<LI>time = tau, where tau = t* = t (epsilon / m / sigma^2)^1/2
+<LI>time = tau, where t* = t (epsilon / m / sigma^2)^1/2
 <LI>energy = epsilon, where E* = E / epsilon
 <LI>velocity = sigma/tau, where v* = v tau / sigma
 <LI>force = epsilon/sigma, where f* = f sigma / epsilon
diff --git a/doc/units.txt b/doc/units.txt
index 3865ecfa70..0806095237 100644
--- a/doc/units.txt
+++ b/doc/units.txt
@@ -42,7 +42,7 @@ results from a unitless LJ simulation into physical quantities.
 
 mass = mass or m
 distance = sigma, where x* = x / sigma
-time = tau, where tau = t* = t (epsilon / m / sigma^2)^1/2
+time = tau, where t* = t (epsilon / m / sigma^2)^1/2
 energy = epsilon, where E* = E / epsilon
 velocity = sigma/tau, where v* = v tau / sigma
 force = epsilon/sigma, where f* = f sigma / epsilon