diff --git a/doc/source/issues.rst b/doc/source/issues.rst
index 44c63113..dbf11894 100644
--- a/doc/source/issues.rst
+++ b/doc/source/issues.rst
@@ -20,6 +20,8 @@ in practice, FLINT defines *slong* and *ulong* types which are guaranteed
 to be 32 bits on a 32-bit system and 64 bits on a 64-bit system.
 They are also guaranteed to have the same size as GMP's :type:`mp_limb_t`.
 GMP builds with a different limb size configuration are not supported at all.
+For convenience, the macro *FLINT_BITS* specifies the word length (32 or 64)
+of the system.
 
 .. type:: slong
 
@@ -29,6 +31,9 @@ GMP builds with a different limb size configuration are not supported at all.
     In method names, an *slong* parameter is denoted by *si*, for example
     :func:`arb_add_si`.
 
+    The constants *WORD_MIN* and *WORD_MAX* give the range of this type.
+    This type can be printed with *flint_printf* using the format string ``%wd``.
+
 .. type:: ulong
 
     The *ulong* type is used for integer-valued coefficients
@@ -37,6 +42,9 @@ GMP builds with a different limb size configuration are not supported at all.
     In method names, a *ulong* parameter is denoted by *ui*, for example
     :func:`arb_add_ui`.
 
+    The constant *UWORD_MAX* gives the range of this type.
+    This type can be printed with *flint_printf* using the format string ``%wu``.
+
 The following GMP-defined types are used in methods that manipulate the
 internal representation of numbers (using limb arrays).