diff --git a/src/Posets.jl b/src/Posets.jl
index 228c925..dcd869b 100644
--- a/src/Posets.jl
+++ b/src/Posets.jl
@@ -10,65 +10,69 @@ using JuMP
 using HiGHS
 
 import Base:
-    eltype, show, ==, +, /, reverse, intersect, getindex, <, <<, >>, issubset, adjoint, in
+    +, /, <, <<, ==, >>, adjoint, eltype, getindex, in, intersect, issubset, reverse, show
 
 import Graphs:
     add_vertex!,
     add_vertices!,
-    add_edge!,
-    rem_vertex!,
-    nv,
-    src,
-    dst,
     connected_components,
+    dst,
+    induced_subgraph,
     is_connected,
-    induced_subgraph
+    nv,
+    rem_vertex!,
+    src
 
 export Poset,
+    Relation,
+    above,
+    add_relation!,
     add_vertex!,
     add_vertices!,
-    rem_vertex!,
-    nv,
-    src,
-    dst,
-    comparability_graph,
-    cover_digraph,
-    vertex_edge_incidence_poset,
-    nr,
-    has_relation,
-    add_relation!,
-    Relation,
-    relations,
-    src,
-    dst,
+    antichain,
     are_comparable,
     are_incomparable,
+    below,
+    between,
+    chain,
+    chain_cover,
+    chevron,
+    comparability_graph,
+    connected_components,
+    cover_digraph,
     covered_by,
-    just_below,
+    dimension,
+    dst,
+    dst,
+    has_relation,
+    height,
+    in,
+    induced_subposet,
+    is_antichain,
+    is_chain,
+    is_connected,
+    iso,
+    iso_check,
     just_above,
+    just_below,
+    linear_extension,
+    max_anti_chain,
+    max_chain,
     maximals,
     minimals,
-    zeta_matrix,
     mobius_matrix,
-    chain,
-    antichain,
+    nr,
+    nv,
+    realizer,
+    relations,
+    rem_vertex!,
+    semiorder,
+    src,
+    src,
     standard_example,
-    chevron,
-    above,
-    below,
-    between,
-    linear_extension,
-    connected_components,
-    is_connected,
-    induced_subposet,
-    in,
-    is_chain,
-    is_antichain,
-    semiorder
-
-# These use integer linear programming.
-export max_anti_chain,
-    max_chain, width, height, chain_cover, realizer, dimension, iso, iso_check
+    vertex_edge_incidence_poset,
+    width,
+    zeta_matrix
 
 function __init__()
     set_solver(HiGHS)