Per-unit ecosystem services value coefficients are wisely used in ecosystem services research, which is usually in the unit of "money per area for certain ecosystem type/services". The ecosystem service evaluation method is known as Benefit transfer method. Many research applied the per-unit ecosystem services value coefficients from Costanza et al. 2014 [1]. Global coefficients for various types of ecosystems are listed in the supplementary material of the article (see the attachment of this question). And for the coefficient of urban system, it says the source is "Ida Kubiszewski: Source: Brenner-Guillermo (2007)", so I searched accordingly and find the article of J Brenner Guillermo[2], published in 2007, but didn't find the coefficient in the article. Did I miss something? Or does anyone know what is the method to get a coefficient for a city and related research? Thank you very much!

Reference:

[1] Costanza, R., de Groot, R., Sutton, P., van der Ploeg, S., Anderson, S.J., Kubiszewski, I., Farber, S., Turner, R.K., 2014. Changes in the global value of ecosystem services. Global Environmental Change 26, 152–158. https://doi.org/10.1016/j.gloenvcha.2014.04.002

[2] Brenner Guillermo, Jorge. Valuation of ecosystem services in the Catalan coastal zone. Universitat Politècnica de Catalunya, 2007. Link: https://upcommons.upc.edu/handle/2117/93710