diff --git a/src/accurate/dw0c.rs b/src/accurate/dw0c.rs
index e9755dd..2593501 100644
--- a/src/accurate/dw0c.rs
+++ b/src/accurate/dw0c.rs
@@ -1,3 +1,5 @@
+//! The original implementation of the principal branch of the Lambert W function by Toshio Fukushima, accurate to 50 bits, ported to Rust.
+
 use crate::LambertW0Error;
 
 /// 50-bit accuracy computation of principal branch of Lambert W function, W_0(z),
diff --git a/src/accurate/dwm1c.rs b/src/accurate/dwm1c.rs
index 599431a..c69554d 100644
--- a/src/accurate/dwm1c.rs
+++ b/src/accurate/dwm1c.rs
@@ -1,3 +1,5 @@
+//! The original implementation of the secondary branch of the Lambert W function by Toshio Fukushima, accurate to 50 bits, ported to Rust.
+
 use super::super::{X0, Z0};
 use crate::{LambertWm1Error, LambertWm1ErrorReason};
 
diff --git a/src/fast/sw0.rs b/src/fast/sw0.rs
index c667a53..8376769 100644
--- a/src/fast/sw0.rs
+++ b/src/fast/sw0.rs
@@ -1,3 +1,5 @@
+//! The original implementation of the principal branch of the Lambert W function by Toshio Fukushima, accurate to 24 bits, ported to Rust.
+
 use super::super::Z0;
 use crate::LambertW0Error;
 
diff --git a/src/fast/swm1.rs b/src/fast/swm1.rs
index bfb5934..d220d6c 100644
--- a/src/fast/swm1.rs
+++ b/src/fast/swm1.rs
@@ -1,3 +1,5 @@
+//! The original implementation of the secondary branch of the Lambert W function by Toshio Fukushima, accurate to 24 bits, ported to Rust.
+
 use super::super::{X0, Z0};
 use crate::{LambertWm1Error, LambertWm1ErrorReason};