Fix broken links

contracts/access/AccessControl.sol

@@ -28,7 +28,7 @@ import "../GSN/Context.sol";
  *
  * Roles can be granted and revoked dynamically via the {grantRole} and
  * {revokeRole} functions. Each role has an associated admin role, and only
- * accounts that have a role's admin role can call {grantRole} and {revokeRoke}.
+ * accounts that have a role's admin role can call {grantRole} and {revokeRole}.
  *
  * By default, the admin role for all roles is `DEFAULT_ADMIN_ROLE`, which means
  * that only accounts with this role will be able to grant or revoke other

contracts/token/ERC20/ERC20.sol

@@ -10,7 +10,7 @@ import "../../utils/Address.sol";
  *
  * This implementation is agnostic to the way tokens are created. This means
  * that a supply mechanism has to be added in a derived contract using {_mint}.
- * For a generic mechanism see {ERC20Mintable}.
+ * For a generic mechanism see {ERC20MinterPauser}.
  *
  * TIP: For a detailed writeup see our guide
  * https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How

contracts/token/ERC20/IERC20.sol

 pragma solidity ^0.6.0;
 
 /**
- * @dev Interface of the ERC20 standard as defined in the EIP. Does not include
- * the optional functions; to access them see {ERC20Detailed}.
+ * @dev Interface of the ERC20 standard as defined in the EIP.
  */
 interface IERC20 {
     /**

contracts/token/ERC777/ERC777.sol

@@ -97,7 +97,7 @@ contract ERC777 is Context, IERC777, IERC20 {
     }
 
     /**
-     * @dev See {ERC20Detailed-decimals}.
+     * @dev See {ERC20-decimals}.
      *
      * Always returns 18, as per the
      * [ERC777 EIP](https://eips.ethereum.org/EIPS/eip-777#backward-compatibility).