DOCS-563 fix links

Author: kay-kim

source/applications.txt

@@ -32,7 +32,7 @@ The following documents outline basic application development topics:
 
    applications/drivers
    applications/database-references
-   core/ObjectId
+   core/object-id
 
 .. seealso:: 
 

source/core/object-id.txt

@@ -2,6 +2,8 @@
 ObjectId
 ========
 
+.. default-domain:: mongodb
+
 :term:`ObjectId <objectid>` is a 12-byte :term:`BSON` type,
 constructed using:
 
@@ -21,7 +23,7 @@ Using ObjectIds for the ``_id`` field, provides the following
 additional benefits:
 
 - you can access the timestamp of the ObjectId's creation, using the
-  :method:`getTimestamp() <ObjectId.getTimeStamp()>` method.
+  :method:`getTimestamp() <ObjectId.getTimestamp()>` method.
 
 - Sorting on an ``_id`` field that stores ObjectId values, is
   equivalent to sorting by creation time.
@@ -35,7 +37,7 @@ The :program:`mongo` shell provides the ``ObjectId()`` wrapper class
 to generate can generate a new ObjectId, and to provide the following
 helper attribute and methods:
 
-- ``str`
+- ``str``
 
    The hexadecimal string value of the ``ObjectID()`` object.
 
@@ -52,7 +54,7 @@ helper attribute and methods:
       In previous versions :method:`ObjectId.toString()>` returns the
       value of the ObjectId as a hexadecimal string.
 
-- :method:``valueOf() <ObjectId.valueOf()>`
+- :method:`valueOf() <ObjectId.valueOf()>`
 
    Returns the value of the ``ObjectId()`` object as a hexadecimal string.
    The returned string is the ``str`` attribute.