diff --git a/l1/1.jl b/l1/1.jl
index 0c53aa9..ca50d29 100755
--- a/l1/1.jl
+++ b/l1/1.jl
@@ -3,7 +3,7 @@
 # Jacek Poziemski 272389
 
 """
-    macheps(T)
+    macheps(T::Type{<: AbstractFloat})
 
 Calculate the machine epsilon iteratively
 for the given IEEE 754 floating point type.
@@ -22,7 +22,7 @@ function macheps(T::Type{<: AbstractFloat})
 end
 
 """
-    eta(T)
+    eta(T::Type{<: AbstractFloat})
 
 Calculate the eta number iteratively
 for the given IEEE 754 floating point type.
@@ -41,7 +41,7 @@ function eta(T::Type{<: AbstractFloat})
 end
 
 """
-    max(T)
+    max(T::Type{<: AbstractFloat})
 
 Calculate the largest possible value
 for the given IEEE 754 floating type.
diff --git a/l1/2.jl b/l1/2.jl
index 3c282a8..09ea4ff 100755
--- a/l1/2.jl
+++ b/l1/2.jl
@@ -3,15 +3,15 @@
 # Jacek Poziemski 272389
 
 """
-    kahanmacheps(T)
+    kahanmacheps(T::Type{<: AbstractFloat})
 
 Calculate the Kahan machine epsilon
 using the following expression: `3(4/3 - 1) - 1`.
 
 # Arguments
-- `T`: a floating point number type <: AbstractFloat
+- `T`: the floating point type
 """
-function kahanmacheps(T)
+function kahanmacheps(T::Type{<: AbstractFloat})
     return T(3) * ((T(4) / T(3)) - one(T)) - one(T)
 end