diff --git a/library/bignum_mod.h b/library/bignum_mod.h
index f1067f0..67684bd 100644
--- a/library/bignum_mod.h
+++ b/library/bignum_mod.h
@@ -26,13 +26,11 @@
  *       parameter is ignored and the final content is unspecified.
  *     - Some functions use different names, such as \p R for the residue.
  * - **Bignum sizes**: bignum sizes are always expressed in limbs. Both
- *   #mbedtls_mpi_mod_modulus and #mbedtls_mpi_mod_residue have a \p limbs
- *   member storing its size. Functions which take a limb array parameter
- *   must also take an associated \p limbs parameter specifying its size.
- *   All bignum sizes must be at least 1 and be significantly less than
- *   #SIZE_MAX. The behavior if a size is 0 may be undefined or an error
- *   may be returned. All bignum parameters must have the same size unless
- *   otherwise specified.
+ *   #mbedtls_mpi_mod_modulus and #mbedtls_mpi_mod_residue have a \c limbs
+ *   member storing its size. All bignum parameters must have the same
+ *   number of limbs as the modulus. All bignum sizes must be at least 1 and
+ *   must be significantly less than #SIZE_MAX. The behavior if a size is 0 is
+ *   undefined.
  * - **Bignum representation**: the representation of inputs and outputs is
  *   specified by the \p int_rep field of the modulus.
  * - **Parameter ordering**: for bignum parameters, outputs come before inputs.
diff --git a/library/bignum_mod_raw.h b/library/bignum_mod_raw.h
index bcdeaad..ddb2d09 100644
--- a/library/bignum_mod_raw.h
+++ b/library/bignum_mod_raw.h
@@ -27,8 +27,8 @@
  *       The initial content of output-only parameters is ignored.
  *     - \p T is a temporary storage area. The initial content of such a
  *       parameter is ignored and the final content is unspecified.
- * - **Bignum sizes**: bignum sizes are always expressed by the \p limbs
- *   member of the modulus argument. Any bignum parameters must have the same
+ * - **Bignum sizes**: bignum sizes are usually expressed by the \c limbs
+ *   member of the modulus argument. All bignum parameters must have the same
  *   number of limbs as the modulus. All bignum sizes must be at least 1 and
  *   must be significantly less than #SIZE_MAX. The behavior if a size is 0 is
  *   undefined.