malformed HTTP header?

[longemen3000]

i'm getting this warning on Downloads v1.6.0, julia 1.8.3, and trying to call api.crossref.org to get BibTeX from doi.

using Downloads
function doi2bib(doi)
    headers = ["Accept"=>"application/x-bibtex",
                "charset" => "utf-8"]
    
    url = "https://api.crossref.org/v1/works/" * doi * "/transform"
    out = IOBuffer()
    r = Downloads.request(url, output = out, method = "GET",headers = headers)
    if r.status == 200
        return String(take!(out))
    else  
        return ""
    end
end

with that function:

dois =  ["10.1021/I160057A011"
 "10.1016/0378-3812(80)80003-3"
 "10.1016/j.fluid.2020.112790"]
for doi in dois
  doi2bib(doi)
end

it gives a warning on the third doi:

┌ Warning: malformed HTTP header
│   url = "https://api.crossref.org/v1/works/10.1063/1.5136079/transform"
│   status = 200
│   header = "link: <http://dx.doi.org/10.1063/1.5136079>; rel=\"canonical\", <http://aip.scitation.org/doi/pdf/10.1063/1.5136079>; version=\"vor\"; rel=\"item\", <http://orcid.org/0000-0002-7436-5825>; title=\"Ailo Aasen\"; rel=\"author\", <http://orcid.org/0000-0002-0921-7527>; title=\"Morten Hammer\"; rel=\"author\", <http://orcid.org/0000-0002-1513-6686>; title=\"Erich A. M\xfcller\"; rel=\"author\"\r\n"