diff --git a/lake-manifest.json b/lake-manifest.json
index 713c8741..972fad06 100644
--- a/lake-manifest.json
+++ b/lake-manifest.json
@@ -1,21 +1,71 @@
 {"version": "1.1.0",
  "packagesDir": ".lake/packages",
  "packages":
- [{"url": "https://github.com/leanprover-community/mathlib4.git",
+ [{"url": "https://github.com/leanprover/doc-gen4.git",
    "type": "git",
    "subDir": null,
    "scope": "",
-   "rev": "c44e0c8ee63ca166450922a373c7409c5d26b00b",
+   "rev": "efe744c75a6ab384619513b9762db1cfc40b0fe4",
+   "name": "«doc-gen4»",
+   "manifestFile": "lake-manifest.json",
+   "inputRev": "v4.20.0",
+   "inherited": false,
+   "configFile": "lakefile.lean"},
+  {"url": "https://github.com/leanprover-community/mathlib4.git",
+   "type": "git",
+   "subDir": null,
+   "scope": "",
+   "rev": "c211948581bde9846a99e32d97a03f0d5307c31e",
    "name": "mathlib",
    "manifestFile": "lake-manifest.json",
-   "inputRev": "v4.19.0",
+   "inputRev": "v4.20.0",
    "inherited": false,
    "configFile": "lakefile.lean"},
+  {"url": "https://github.com/mhuisi/lean4-cli",
+   "type": "git",
+   "subDir": null,
+   "scope": "",
+   "rev": "4f22c09e7ded721e6ecd3cf59221c4647ca49664",
+   "name": "Cli",
+   "manifestFile": "lake-manifest.json",
+   "inputRev": "main",
+   "inherited": true,
+   "configFile": "lakefile.toml"},
+  {"url": "https://github.com/fgdorais/lean4-unicode-basic",
+   "type": "git",
+   "subDir": null,
+   "scope": "",
+   "rev": "45c426d1cb016fcb4fcbe043f1cd2d97acb2dbc3",
+   "name": "UnicodeBasic",
+   "manifestFile": "lake-manifest.json",
+   "inputRev": "main",
+   "inherited": true,
+   "configFile": "lakefile.lean"},
+  {"url": "https://github.com/dupuisf/BibtexQuery",
+   "type": "git",
+   "subDir": null,
+   "scope": "",
+   "rev": "dbfe2b7630c5f7c5c1cf71e7747ffc0a30337f69",
+   "name": "BibtexQuery",
+   "manifestFile": "lake-manifest.json",
+   "inputRev": "master",
+   "inherited": true,
+   "configFile": "lakefile.toml"},
+  {"url": "https://github.com/acmepjz/md4lean",
+   "type": "git",
+   "subDir": null,
+   "scope": "",
+   "rev": "8ba0ef10d178ab95a5d6fe3cfbd586c6ecef2717",
+   "name": "MD4Lean",
+   "manifestFile": "lake-manifest.json",
+   "inputRev": "main",
+   "inherited": true,
+   "configFile": "lakefile.lean"},
   {"url": "https://github.com/leanprover-community/plausible",
    "type": "git",
    "subDir": null,
    "scope": "leanprover-community",
-   "rev": "77e08eddc486491d7b9e470926b3dbe50319451a",
+   "rev": "2ac43674e92a695e96caac19f4002b25434636da",
    "name": "plausible",
    "manifestFile": "lake-manifest.json",
    "inputRev": "main",
@@ -25,7 +75,7 @@
    "type": "git",
    "subDir": null,
    "scope": "leanprover-community",
-   "rev": "25078369972d295301f5a1e53c3e5850cf6d9d4c",
+   "rev": "6c62474116f525d2814f0157bb468bf3a4f9f120",
    "name": "LeanSearchClient",
    "manifestFile": "lake-manifest.json",
    "inputRev": "main",
@@ -35,7 +85,7 @@
    "type": "git",
    "subDir": null,
    "scope": "leanprover-community",
-   "rev": "e6a9f0f5ee3ccf7443a0070f92b62f8db12ae82b",
+   "rev": "a11bcb5238149ae5d8a0aa5e2f8eddf8a3a9b27d",
    "name": "importGraph",
    "manifestFile": "lake-manifest.json",
    "inputRev": "main",
@@ -45,17 +95,17 @@
    "type": "git",
    "subDir": null,
    "scope": "leanprover-community",
-   "rev": "c4919189477c3221e6a204008998b0d724f49904",
+   "rev": "21e6a0522cd2ae6cf88e9da99a1dd010408ab306",
    "name": "proofwidgets",
    "manifestFile": "lake-manifest.json",
-   "inputRev": "v0.0.57",
+   "inputRev": "v0.0.60",
    "inherited": true,
    "configFile": "lakefile.lean"},
   {"url": "https://github.com/leanprover-community/aesop",
    "type": "git",
    "subDir": null,
    "scope": "leanprover-community",
-   "rev": "5d50b08dedd7d69b3d9b3176e0d58a23af228884",
+   "rev": "ddfca7829bf8aa4083cdf9633935dddbb28b7b2a",
    "name": "aesop",
    "manifestFile": "lake-manifest.json",
    "inputRev": "master",
@@ -65,7 +115,7 @@
    "type": "git",
    "subDir": null,
    "scope": "leanprover-community",
-   "rev": "fa4f7f15d97591a9cf3aa7724ba371c7fc6dda02",
+   "rev": "2865ea099ab1dd8d6fc93381d77a4ac87a85527a",
    "name": "Qq",
    "manifestFile": "lake-manifest.json",
    "inputRev": "master",
@@ -75,21 +125,11 @@
    "type": "git",
    "subDir": null,
    "scope": "leanprover-community",
-   "rev": "f5d04a9c4973d401c8c92500711518f7c656f034",
+   "rev": "7a0d63fbf8fd350e891868a06d9927efa545ac1e",
    "name": "batteries",
    "manifestFile": "lake-manifest.json",
    "inputRev": "main",
    "inherited": true,
-   "configFile": "lakefile.toml"},
-  {"url": "https://github.com/leanprover/lean4-cli",
-   "type": "git",
-   "subDir": null,
-   "scope": "leanprover",
-   "rev": "02dbd02bc00ec4916e99b04b2245b30200e200d0",
-   "name": "Cli",
-   "manifestFile": "lake-manifest.json",
-   "inputRev": "main",
-   "inherited": true,
    "configFile": "lakefile.toml"}],
  "name": "glimpseOfLean",
  "lakeDir": ".lake"}
diff --git a/lakefile.toml b/lakefile.toml
index 071ee52e..c589677f 100644
--- a/lakefile.toml
+++ b/lakefile.toml
@@ -8,7 +8,12 @@ autoImplicit = true
 [[require]]
 name = "mathlib"
 git = "https://github.com/leanprover-community/mathlib4.git"
-rev = "v4.19.0"
+rev = "v4.20.0"
+
+[[require]]
+name = "doc-gen4"
+git = "https://github.com/leanprover/doc-gen4.git"
+rev = "v4.20.0"
 
 [[lean_lib]]
 name = "GlimpseOfLean"
diff --git a/lean-toolchain b/lean-toolchain
index 7aca1d8a..5e485899 100644
--- a/lean-toolchain
+++ b/lean-toolchain
@@ -1 +1 @@
-leanprover/lean4:v4.19.0
+leanprover/lean4:v4.20.0
\ No newline at end of file