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We present an extension of our search for Extremely Inverted SpectrumExtragalactic Radio Sources (EISERS) to the northern celestial hemisphere. Withan inverted radio spectrum of slope $\alpha$ > +2.5, these rare sources wouldeither require a non-standard particle acceleration mechanism (in the frameworkof synchrotron self-absorption hypothesis), or a severe free-free absorptionwhich attenuates practically all of their synchrotron radiation at metrewavelengths. By applying a sequence of selection filters, a list of 15 EISERScandidates is extracted out by comparing two large-sky radio surveys, WENSS(325 MHz) and TGSS-ADR1 (150 MHz), which overlap across 1.03$\pi$ steradian ofthe sky. Here we report quasi-simultaneous GMRT observations of these 15 EISERScandidates at 150 MHz and 325 MHz, in an attempt to accurately define theirspectra below the turnover frequency. Out of the 15 candidates observed, twoare confirmed as EISERS, since the slope of the inverted spectrum between thesetwo frequencies is found to be significantly larger than the critical value$\alpha_c$ = +2.5: the theoretical limit for the standard case of synchrotronself-absorption (SSA). For another 3 sources, the spectral slope is close to,or just above the critical value $\alpha_c$. Nine of the sources have GPS typeradio spectra. The parsec-scale radio structural information available for thesample is also summarised.

GMRT observations of a first sample of Extremely Inverted Spectrum Extragalactic Radio Sources (EISERS) candidates in the Northern sky