diff --git a/docs/api.rst b/docs/api.rst
index a685482c..167743b1 100644
--- a/docs/api.rst
+++ b/docs/api.rst
@@ -125,3 +125,20 @@ Line search
   :toctree: _autosummary
 
     jaxopt.BacktrackingLineSearch
+
+Tree utilities
+--------------
+
+.. autosummary::
+  :toctree: _autosummary
+
+    jaxopt.tree_util.tree_add
+    jaxopt.tree_util.tree_sub
+    jaxopt.tree_util.tree_mul
+    jaxopt.tree_util.tree_div
+    jaxopt.tree_util.tree_scalar_mul
+    jaxopt.tree_util.tree_add_scalar_mul
+    jaxopt.tree_util.tree_vdot
+    jaxopt.tree_util.tree_sum
+    jaxopt.tree_util.tree_l2_norm
+    jaxopt.tree_util.tree_zeros_like
diff --git a/docs/changelog.rst b/docs/changelog.rst
index b781d07f..74916a15 100644
--- a/docs/changelog.rst
+++ b/docs/changelog.rst
@@ -7,9 +7,10 @@ Version 0.3
 New features
 ~~~~~~~~~~~~
 
-- :class:`jaxopt.LBFGS`.
-- :class:`jaxopt.BacktrackingLineSearch`.
-- :class:`jaxopt.GaussNewton`.
+- :class:`jaxopt.LBFGS`
+- :class:`jaxopt.BacktrackingLineSearch`
+- :class:`jaxopt.GaussNewton`
+- :class:`jaxopt.NonlinearCG`
 
 Bug fixes and enhancements
 ~~~~~~~~~~~~~~~~~~~~~~~~~~
@@ -17,6 +18,11 @@ Bug fixes and enhancements
 - `Support implicit AD in higher-order differentiation
   <https://github.com/google/jaxopt/pull/143>`_.
 
+Contributors
+~~~~~~~~~~~~
+
+Amir Saadat, Fabian Pedregosa, Geoffrey Négiar, Hyunsung Lee, Mathieu Blondel, Roy Frostig.
+
 Version 0.2
 -----------
 
@@ -48,7 +54,7 @@ Bug fixes and enhancements
 Deprecations
 ~~~~~~~~~~~~
 
-- :class:`jaxopt.QuadraticProgramming` is deprecated and will be removed in v0.3. Use
+- :class:`jaxopt.QuadraticProgramming` is deprecated and will be removed in v0.4. Use
   :class:`jaxopt.CvxpyQP`, :class:`jaxopt.OSQP`, :class:`jaxopt.BoxOSQP` and
   :class:`jaxopt.EqualityConstrainedQP` instead.
 - ``params, state = solver.init(...)`` is deprecated. Use ``state = solver.init_state(...)`` instead.
diff --git a/docs/unconstrained.rst b/docs/unconstrained.rst
index e1a3b1b1..6ba29fcf 100644
--- a/docs/unconstrained.rst
+++ b/docs/unconstrained.rst
@@ -53,7 +53,8 @@ instantiated and run as follows::
   # Alternatively, we could have used one of these solvers as well:
   # solver = jaxopt.GradientDescent(fun=ridge_reg_objective, maxiter=500)
   # solver = jaxopt.ScipyMinimize(fun=ridge_reg_objective, method="L-BFGS-B", maxiter=500)
-  # cg_model = jaxopt.NonlinearCG(fun=ridge_reg_objective, maxiter=300, method="polak-ribiere")
+  # solver = jaxopt.NonlinearCG(fun=ridge_reg_objective, method="polak-ribiere", maxiter=500)
+
 Unpacking results
 ~~~~~~~~~~~~~~~~~
 
diff --git a/jaxopt/_src/quadratic_prog.py b/jaxopt/_src/quadratic_prog.py
index e63166b7..3d279c6f 100644
--- a/jaxopt/_src/quadratic_prog.py
+++ b/jaxopt/_src/quadratic_prog.py
@@ -158,7 +158,7 @@ def ineq_fun(primal_var, params_ineq):
 
 @dataclass(eq=False)
 class QuadraticProgramming(base.Solver):
-  """Deprecated: will be removed in v0.3.
+  """Deprecated: will be removed in v0.4.
 
   Use :class:`jaxopt.CvxpyQP`, :class:`jaxopt.OSQP`, :class:`jaxopt.BoxOSQP` and
   :class:`jaxopt.EqualityConstrainedQP` instead.
@@ -233,7 +233,7 @@ def l2_optimality_error(
     return tree_util.tree_l2_norm(pytree)
 
   def __post_init__(self):
-    warnings.warn("Class 'QuadraticProgramming' will be removed in v0.3. "
+    warnings.warn("Class 'QuadraticProgramming' will be removed in v0.4. "
                   "Use 'EqualityConstraintsQP' if you want the same behavior as "
                   "'QuadraticProgramming' for QPs with equality constraints only. "
                   "Use 'CVXPY_QP' if you want the same behavior as "
diff --git a/jaxopt/_src/tree_util.py b/jaxopt/_src/tree_util.py
index 3521a643..393056cd 100644
--- a/jaxopt/_src/tree_util.py
+++ b/jaxopt/_src/tree_util.py
@@ -31,9 +31,16 @@
 tree_unflatten = tu.tree_unflatten
 
 tree_add = functools.partial(tree_multimap, operator.add)
+tree_add.__doc__ = "Tree addition."
+
 tree_sub = functools.partial(tree_multimap, operator.sub)
+tree_sub.__doc__ = "Tree subtraction."
+
 tree_mul = functools.partial(tree_multimap, operator.mul)
+tree_mul.__doc__ = "Tree multiplication."
+
 tree_div = functools.partial(tree_multimap, operator.truediv)
+tree_div.__doc__ = "Tree division."
 
 
 def tree_scalar_mul(scalar, tree_x):