diff --git a/docs/src/literate-tutorials/heat_equation.jl b/docs/src/literate-tutorials/heat_equation.jl
index 2f8599e..0102ca2 100644
--- a/docs/src/literate-tutorials/heat_equation.jl
+++ b/docs/src/literate-tutorials/heat_equation.jl
@@ -37,7 +37,7 @@
 # The resulting weak form is given given as follows: Find ``u \in \mathbb{U}`` such that
 # ```math
 #  \int_{\Omega} \nabla \delta u \cdot \nabla u \mathrm{d}\Omega
-#  \int_{\Gamma^{\text{P}/\text{M}}} [\![ \delta u ]\!] [\![ u ]\!] \mathrm{d}\Gamma
+#  + \int_{\Gamma^{\text{P}/\text{M}}} [\![ \delta u ]\!] [\![ u ]\!] \mathrm{d}\Gamma
 #  = 0 \quad \forall \delta u \in \mathbb{T},
 # ```
 # where $\delta u$ is a test function, and where $\mathbb{U}$ and $\mathbb{T}$ are suitable
@@ -259,4 +259,4 @@ CairoMakie.save("heat_equation_result.png", fig);
 #md #
 #md # ```julia
 #md # @__CODE__
-#md # ```
\ No newline at end of file
+#md # ```
diff --git a/src/grid.jl b/src/grid.jl
index e2aa58c..9af4bd6 100644
--- a/src/grid.jl
+++ b/src/grid.jl
@@ -7,8 +7,8 @@
 
 Return a new grid with `InterfaceCell`s inserted betweenthe domains defined by `domain_names`.
 The new grid provides additional cell sets. The set `"interfaces"` contains all new `InterfaceCell`s
-and two sets are provided for each combination of domain names: `"domain1-domain2-inertface"` and 
-`"domain2-domain1-inertface"` both using the same `Set`.
+and two sets are provided for each combination of domain names: `"domain1-domain2-interface"` and 
+`"domain2-domain1-interface"` both using the same `Set`.
 """
 function insert_interfaces(grid, domain_names; topology=ExclusiveTopology(grid))
     cellsets = Dict(name => getcellset(grid, name) for name in domain_names)