Given the following context:

"Shine" received mixed reviews from music critics. E! News' Bruna Nessif gave the single a positive review, stating: "When it comes to feel-good music, leave it up to Gwen Stefani and Pharrell to get the job done". A reviewer from Vibe praised it as "the perfect theme song". Abe Dewing, a member of the Cambridge Symphony Orchestra, described it as a "sharp, hip tune" in the Boston Herald. He compared its opening trumpet riff to music by British composer Herbert Chappell, who created the theme for the 1975 television series Paddington. Chappell also composed music for the 1986 concerto "Paddington Bear's First Concert". Dewing praised Stefani and Willams' ability "to compose new music for existing source material intended for children". A reviewer from the website antiMusic described the recording as "even more feel good" than the pair's collaboration on "Spark the Fire". Daniel Sannwald gave it three and a half stars out of five, favorably comparing its melody to the chorus of Irish rock band The Cranberries's 1994 single "Zombie". He felt that it would appeal to both children and their parents.Some reviewers criticized "Shine" for lacking the energy of Williams' and Stefani's previous releases. MTV's John Walker questioned whether it could repeat the success of Williams' previous single "Happy" from the 2013 animated film Despicable Me 2. In response to the leaked version, Carolyn Menyes wrote that it was too slow in comparison to the "crazy, happy beats and earwormmy hand claps" of "Happy" and the "inane catchiness" of Stefani's previous singles "Spark the Fire" and "Baby Don't Lie" (2014). Menyes was critical of Stefani's vocals, saying she used "an oddly harsh tone" throughout the track. Steven Pond of TheWrap wrote that Stefani's vocal delivery "never quite crosses the line to catchy".

answer the following question:

What is the full names of the people that collaborated on Spark the Fire? 

Gwen Stefani