diff --git a/src/blockdata/opcodes.rs b/src/blockdata/opcodes.rs
index f305115b..5623f758 100644
--- a/src/blockdata/opcodes.rs
+++ b/src/blockdata/opcodes.rs
@@ -385,9 +385,9 @@ pub mod all {
     pub const OP_HASH256: All = All {code: 0xaa};
     /// Ignore this and everything preceding when deciding what to sign when signature-checking
     pub const OP_CODESEPARATOR: All = All {code: 0xab};
-    /// https://en.bitcoin.it/wiki/OP_CHECKSIG pushing 1/0 for success/failure
+    /// <https://en.bitcoin.it/wiki/OP_CHECKSIG> pushing 1/0 for success/failure
     pub const OP_CHECKSIG: All = All {code: 0xac};
-    /// https://en.bitcoin.it/wiki/OP_CHECKSIG returning success/failure
+    /// <https://en.bitcoin.it/wiki/OP_CHECKSIG> returning success/failure
     pub const OP_CHECKSIGVERIFY: All = All {code: 0xad};
     /// Pop N, N pubkeys, M, M signatures, a dummy (due to bug in reference code), and verify that all M signatures are valid.
     /// Push 1 for "all valid", 0 otherwise
@@ -396,9 +396,9 @@ pub mod all {
     pub const OP_CHECKMULTISIGVERIFY: All = All {code: 0xaf};
     /// Does nothing
     pub const OP_NOP1: All = All {code: 0xb0};
-    /// https://github.com/bitcoin/bips/blob/master/bip-0065.mediawiki
+    /// <https://github.com/bitcoin/bips/blob/master/bip-0065.mediawiki>
     pub const OP_CLTV: All = All {code: 0xb1};
-    /// https://github.com/bitcoin/bips/blob/master/bip-0112.mediawiki
+    /// <https://github.com/bitcoin/bips/blob/master/bip-0112.mediawiki>
     pub const OP_CSV: All = All {code: 0xb2};
     /// Does nothing
     pub const OP_NOP4: All = All {code: 0xb3};
diff --git a/src/util/bip32.rs b/src/util/bip32.rs
index 26dbbe03..0934af0f 100644
--- a/src/util/bip32.rs
+++ b/src/util/bip32.rs
@@ -14,7 +14,7 @@
 //! BIP32 Implementation
 //!
 //! Implementation of BIP32 hierarchical deterministic wallets, as defined
-//! at https://github.com/bitcoin/bips/blob/master/bip-0032.mediawiki
+//! at <https://github.com/bitcoin/bips/blob/master/bip-0032.mediawiki>
 
 use std::default::Default;
 use std::{error, fmt};
diff --git a/src/util/contracthash.rs b/src/util/contracthash.rs
index 271f8a63..3e8a4809 100644
--- a/src/util/contracthash.rs
+++ b/src/util/contracthash.rs
@@ -15,7 +15,7 @@
 //! Pay-to-contract-hash support
 //!
 //! See Appendix A of the Blockstream sidechains whitepaper
-//! at http://blockstream.com/sidechains.pdf for details of
+//! at <http://blockstream.com/sidechains.pdf> for details of
 //! what this does.
 
 #![cfg_attr(not(test), deprecated)]
diff --git a/src/util/psbt/mod.rs b/src/util/psbt/mod.rs
index 4f9c54dd..9cf69403 100644
--- a/src/util/psbt/mod.rs
+++ b/src/util/psbt/mod.rs
@@ -15,7 +15,7 @@
 //! # Partially Signed Transactions
 //!
 //! Implementation of BIP174 Partially Signed Bitcoin Transaction Format as
-//! defined at https://github.com/bitcoin/bips/blob/master/bip-0174.mediawiki
+//! defined at <https://github.com/bitcoin/bips/blob/master/bip-0174.mediawiki>
 //! except we define PSBTs containing non-standard SigHash types as invalid.
 
 use blockdata::script::Script;
diff --git a/src/util/psbt/raw.rs b/src/util/psbt/raw.rs
index 44f80d03..2e9d98e4 100644
--- a/src/util/psbt/raw.rs
+++ b/src/util/psbt/raw.rs
@@ -15,7 +15,7 @@
 //! # Raw PSBT Key-Value Pairs
 //!
 //! Raw PSBT key-value pairs as defined at
-//! https://github.com/bitcoin/bips/blob/master/bip-0174.mediawiki.
+//! <https://github.com/bitcoin/bips/blob/master/bip-0174.mediawiki>.
 
 use std::{fmt, io};