[1] A. D. ALEXANDROFF: 
Additive set functions in abstract spaces. Mat. Sbornik 50 (1940), 30-348; 51 (1941), 563-628; 55 (1943), 169-238. 
MR 0012207 | 
Zbl 0023.39701[2] R. L. BLAIR A. W. HAGER: 
Extensions of zero-sets and of real-valued functions. Math. Zeit. 136 (1974), 41-52. 
MR 0385793[4] Z. FROLÍK: 
Three uniform spaces associated with realvalued functions. Proc. Rome conference on rings of continuous functions 1973, to appear. 
MR 0375243[5] Z. FROLÍK: 
On uniform spaces. Comment. Math. Univ. Carolinae 16 (1975), 189-199. 
MR 0370516[6] L. GILLMAN M. JERISON: 
Rings of Continuous Functions. D. van Nostrand Co., 1960. 
MR 0116199[7] H. GORDON: 
Rings of functions determined by zero-sets. Pac. J. Math. 36 (1971), 1331-157. 
MR 0320996 | 
Zbl 0185.38803[8] A. W. HAGER: 
On inverse-closed subalgebras of $C(X)$. Proc. London Math. Soc. (3) 19 (1969), 233-257. 
MR 0244948 | 
Zbl 0169.54005[9] A. W. HAGER: 
An approximation technique for real-valued functions. Gen. Top. and Appl. 1 (1971), 415-418. 
MR 0291704 | 
Zbl 0219.54010[10] A. W. HAGER: 
An approximation technique for real-valued functions, 2. preprint 1972. 
MR 0291704[11] A. W. HAGER: 
Some nearly fine uniform spaces. Proc. London Math. Soc. (3) 28 (1974), 517-546. 
MR 0397670 | 
Zbl 0284.54017[12] A. W. HAGER: Uniformities induced by proximity, cozero- and Baire sets. to appear.
[13] P. HAUSDORFF: 
Set Theory. (Chelsea Reprint) New York, 1957. 
Zbl 0081.04601[14] R. D. MAULDIN: 
On the Baire system generated by a linear lattice of functions. Fund. Math. 68 (1970), 51-59. 
MR 0273363 | 
Zbl 0197.38104[15] S. G. MRÓWKA: 
Characterization of classes of functions by Lebesque sets. Czech. Math. J. 19 (1969), 738-744. 
MR 0248291