The phrase "are calling for further" is correct and usable in written English.
It can be used when expressing a demand or request for additional action, information, or resources.
Example: "The community leaders are calling for further support from the government to address the ongoing crisis."
Alternatives: "are requesting additional" or "are urging for more".
Some families are calling for further action.
They are calling for further study into the likely impact of Turkey's inclusion in the alliance.
But the possible dangers of injecting people with nanoparticles are a general concern among some researchers and activist groups, who are calling for further study.
But now that online dating is a billion-dollar industry, state officials, public safety advocates and enterprising businesses are calling for further safeguards.
Now on this year's TUC agenda, it is noticeable that it is only the PCS, NUT and UCU unions that are calling for further industrial action on pensions and the co-ordination of that action.
Both doctors are calling for further investigation into the implications of vitamin D deficiency and highlighting the need to be aware of rickets in cases of Sids, which can be mistaken for non-accidental injury.
Indeed, a few enlightened nanotechnologists, notably those at Rice University's Center for Biological and Environmental Nanotechnology (CBEN), have for several years been calling for further research on the biological effects of nanomaterials.
Before the fiscal battle flared up, regulators were calling for further measures to strengthen both the Wall Street debt market and the money market funds.
Mr. Clinton adopted the rules even though Congress was calling for further study to determine whether there was adequate scientific basis for ergonomics rules to reduce the 1.8 million injuries reported each year.
The Labour Party is calling for further investigation.
Defcon, for his part, is calling for further decentralization of online markets and currency.
