diff --git a/src/PDSProblemLibrary.jl b/src/PDSProblemLibrary.jl
index fe654741..998f5b64 100644
--- a/src/PDSProblemLibrary.jl
+++ b/src/PDSProblemLibrary.jl
@@ -92,7 +92,7 @@ u_2' &=  0.04u_1-10^4 u_2u_3-3⋅10^7 u_2^2,\\\\
 u_3' &= 3⋅10^7 u_2^2,
 \\end{aligned}
 ```
-with initial value ``\\mathbf{u}_0 = (1.0, 0.0, 0.0)^T`` and time domain ``(0.0, 10^11)``.
+with initial value ``\\mathbf{u}_0 = (1.0, 0.0, 0.0)^T`` and time domain ``(0.0, 10^{11})``.
 There is one independent linear invariant, e.g. ``u_1+u_2+u_3 = 1.0``.
 
 ## References
diff --git a/src/mprk.jl b/src/mprk.jl
index 5b8e8878..65594914 100644
--- a/src/mprk.jl
+++ b/src/mprk.jl
@@ -751,7 +751,7 @@ non-negative Runge--Kutta coefficients.
 Each member of this family is a one-step method with four-stages which is
 third-order accurate, unconditionally positivity-preserving, conservative and linearly
 implicit. In this implementation the stage-values are conservative as well. The parameter `γ` must satisfy
-`\\frac{3}{8}≤ γ≤\\frac{3}{4}`. 
+`3/8 ≤ γ ≤ 3/4`. 
 Further details are given in Kopecz and Meister (2018).  
 
 These modified Patankar-Runge-Kutta methods require the special structure of a