[1] Banakh T.: 
$\rm AE(0)$–spaces and regular operators extending (averaging) pseudometrics. Bull. Polish Acad. Sci. Math. 42 (1994), no. 3, 197–206. 
MR 1811849 
[2] Bessaga C.: 
On linear operators and functors extending pseudometrics. Fund. Math. 142 (1993), no. 2, 101-122. 
MR 1211761 | 
Zbl 0847.54033 
[4] George A., Veeramani P.: 
On some results of analysis for fuzzy metric spaces. Fuzzy Sets and Systems 90 (1997), 365–368. 
MR 1477836 | 
Zbl 0917.54010 
[5] Gregori V., Morillas S., Sapena A.: 
On a class of completable fuzzy metric spaces. Fuzzy Sets and Systems 161 (2010), 2193–2205. 
MR 2652720 | 
Zbl 1201.54011 
[7] Hausdorff F.: Erweiterung einer Homöomorphie. Fund. Math. 16 (1930), 353–360.
[10] Narici L., Beckenstein E.: 
Topological vector spaces. Pure and Applied Mathematics, 95, Marcel Dekker, New York-Basel, 1985. 
MR 0812056 | 
Zbl 1219.46001 
[12] Repovš D., Savchenko A., Zarichnyi M.: 
Fuzzy Prokhorov metric on the set of probability measures. Fuzzy Sets and Systems 175 (2011), 96–104. 
MR 2803416 
[13] Savchenko A.: 
Extension of fuzzy metrics. Carpathian Mathematical Publications 2 (2010), no. 2, 111–115 (in Ukrainian). 
Zbl 1224.54020 
[15] Stasyuk I., Tymchatyn E.D.: 
A continuous operator extending ultrametrics. Comment. Math. Univ. Carolin. 50 (2009), no. 1, 141–151. 
MR 2562811 | 
Zbl 1212.54091 
[16] Stasyuk I., Tymchatyn E.D.: On continuous linear operators extending metrics. submitted to Proc. Amer. Math. Soc.
[18] Tymchatyn E.D., Zarichnyi M.: 
A note on operators extending partial ultrametrics. Comment. Math. Univ. Carolin. 46 (2005), no. 3, 515–524. 
MR 2174529 | 
Zbl 1121.54045 
[19] Zarichnyi M.: 
Regular linear operators extending metrics: a short proof. Bull. Polish Acad. Sci. Math. 44 (1996), no. 3, 267–269. 
MR 1419399 | 
Zbl 0866.54017