When I am providing credit for documentation / examples / studies taken from other websites, it is enough to name the website or do I need to include something extra, like a foot note about the source?
This is within the context of a sales letter.
Here is a generic example:
According to a study conducted by the website ContentMarketingInstitute.com, the top five challenges of B2B content marketers are:
#1 - Producing engaging content (60%)
#2 - Measuring content effectiveness (57%).
#3 - Producing content consistently (57%).
#4 - Measuring the ROI of content marketing programs (52%).
#5 - A lack of budget (35%).
Also, when providing credit in a sales letter (or any published material), do you provide credit to the original source or the site on which the data is published? For example, let's say that CopyBlogger provides some statistics about content consumption. These statistics are taken from another site and this is mentioned on CopyBlogger.
If I provide this as a form of documentation, do I give credit to CopyBlogger or to the original website?