§§ is a typographical Symbole which is used to indicate several paragraphs of the same work (for example, “to see work of G., chap.6, §§ 7 to 10. ”). To indicate only one paragraph, to use “§”.

Similar cases:

• Sir, shortened by “Mr.” and Sirs, by “Misters”
• page, shortened by “p.” (p. 851) will be in the plural “pp.” (pp. 850-852)

See too

• §