and served as the benchmark for the [<span style="font-variant:small-caps;">NEUT</span>]{}development of both models. The implementation of the SF model in NuWro was based on the code written for Reference [@Ankowski:2007uy] and subsequently optimized for NuWro. The Nieves model implementation in NuWro used a series of lookup tables for the 2p2h cross-section as a function of leptonic variables for various nuclear targets and neutrino species so is very similar as in [<span style="font-variant:small-caps;">NEUT</span>]{}, although it has since been improved to use a more general formalism which depends on a number of nuclear response functions which can be extracted from the Nieves code, and therefore reduces the number of lookup tables required. The same generic model [@multinucleon] was used to simulate the initial and final hadronic states in NuWro as was used in [<span style="font-variant:small-caps;">NEUT</span>]{}. For both the SF and Nieves 2p2h models, NuWro and [<span style="font-variant:small-caps;">NEUT</span>]{}are in good agreement, which provides a useful validation of the [<span style="font-variant:small-caps;">NEUT</span>]{}implementations of these models.

External datasets {#sec:extdata}
=================

Four datasets are used in the CCQE fits presented in this work: the [MiniBooNE]{}neutrino [@mb-ccqe-2010] (2010) and antineutrino [@mb-ccqe-antinu-2013] (2013) results; and the [MINER$\nu$A]{}neutrino [@minerva-nu-ccqe] (2013) and antineutrino [@minerva-antinu-ccqe] (2013) results. All experimental details and information about 