The magic item creation guidelines say:

Note that all items have prerequisites in their descriptions. These prerequisites must be met for the item to be created. Most of the time, they take the form of spells that must be known by the item’s creator (although access through another magic item or spellcaster is allowed).
So, a wizard with Craft Wondrous Item can make an amulet of natural armor if his druid buddy with no item creation feats casts the barkskin spell for him as needed.

But then under the section on creating scrolls, it says:

The creator must have prepared the spell to be scribed (or must know the spell...)...
Does this specifically prohibit the commonly referenced approach on these boards of having one caster with the feat scribing scrolls of unusual spells without needing the person who can actually cast them to have Scribe Scroll? For example, an archivist scribing those low-level half-caster or rare domain spells using his own feat but the caster's spell slot? Or less cheesily, a wizard expanding his spellbook by collaborating with a cleric buddy who prepares spells common to both lists for the wizard to scribe and then add to his spellbook?